摘要
生长素是最早被发现的一种植物激素,极性运输的特性是其区别于多种植物激素的独有特征。目前,人们普遍认为生长素输入输出载体在细胞质膜上的不均匀分布实现了生长素的极性运输,并建立了生长素在植物体内的梯度分布。生长素的极性运输参与了植物许多重要的生长发育过程,其中包括植物的分枝、向性生长和根系的生长发育等。生长素及其极性运输不仅影响植物的形态特征,而且和矿质元素的吸收,运输和分布之间存在着密切的联系,矿质营养与植物内源激素的相互关系一直是植物营养研究的重要内容。
PIN蛋白家族是目前研究较多的生长素输出载体。在拟南芥中,PIN基因家族一共克隆到了8个基因；水稻中预测到12个PIN的同源基因。OsPIN2是水稻中一个可能的生长素输出载体,我们通过转基因手段对OsPIN2在水稻中的生理功能进行了研究,确定该基因在调控水稻株型、根系生长发育及磷素营养吸收转运方面具有重要作用。主要研究结果如下：
1.通过生物信息学分析表明OSPIN2基因位于第6号染色体,其全长基因由7个外显子及6个内含子组成。跨膜结构分析结果显示该基因编码的蛋白在N端和C端含有两个大的跨膜结构域,其间由一个较大的中央亲水环相连。与已报道的其它植物的PIN2蛋白序列联配比较发现,PIN2蛋白两个大的跨膜区域在不同植物间具有高度保守性,但在中间亲水区域存在差异。亚细胞定位结果也证实OsPIN2是一个质膜蛋白。
2.利用植物双元表达载体pCAMBIA1390-ubi,获得了单拷贝插入、未破坏功能基因且OsPIN2基因表达量显著上调的两个超表达株系O1和O2。表型分析发现：OSPIN2基因的过量表达导致水稻分蘖角度增大两倍、分蘖数目平均增多30%和株高变矮。此外,01和02的穗长和单稳重减小,种子的长度、宽度及千粒重减小,结实率不变。
3.利用IAA的HPLC直接测定法与DR5::GUS二次转基因染色观察法相结合,研究结果显示超表达植株倒一叶叶片及叶鞘、倒二叶叶片及叶鞘的生长素浓度降低(超表达材料倒一、倒二叶叶片的生长素浓度是野生型的11%-35%；倒一叶叶鞘的生长素浓度与WT没有显著差异,但倒二叶叶鞘的低于WT,是野生型的380%-53%)；根茎结合处及根系的三个不同区段生长素浓度提高(在根茎结合处比WT增长了65%o-128%)。利用生长素极性运输抑制剂NPA处理WT及O1、O2,发现超表达植株对NPA的抗性增强。这些结果说明,OsPIN2过量表达后改变了水稻体内生长素的运输模式和分布方式。
4.利用半定量RT-PCR分析水稻分蘖角度相关基因OSLazyl和OsTACl,以及另一个可能调控分蘖角度的生长素极性输出蛋白基因OsPINlb在WT、O1和02根系及叶片中的表达量,发现在超表达材料的叶片中OSLazyl基因表达量明显下调,而其它两个基因的表达没有明显变化,由此我们得出实验结论：OSPIN2超表达可能通过调节控制水稻分蘖角度基因OSLazyl的表达量来调控水稻分蘖角度。
5.正常供磷条件下,水稻OsPIN2超表达材料的不定根数目减少(35天苗龄),侧根密度降低,总根长减小,根毛密度增加。缺磷处理可以诱导水稻根长(最长不定根长)、不定根数目和平均侧根长增加,但是当生长素极性运输抑制剂NPA存在时这些根系特征参数的变化幅度均显著减小。利用NPA结合不同磷浓度处理WT、01、02的实验,我们证明了生长素极性运输参与单子叶植物水稻缺磷根构型的改变。
6.水稻OsPIN2超表达材料除了地上部及根系的形态特征发生改变,其磷素营养的吸收转运和分配也受到了影响。通过对正常供磷和缺磷水培条件下WT、01、02根系及地上部总磷浓度的测定及水稻磷酸盐转运蛋白Pht1家族基因表达丰度的分析,我们推测超表达材料由于根毛的大量发生导致根系中总的磷浓度提高。我们还研究了生长素对水稻生长发育后期磷素营养转运分配的影响。通过测定灌浆前期与成熟期WT、01、02营养器官和生殖器官总的氮磷浓度,我们发现OsPIN2超表达延迟了水稻体内的磷素由营养器官向生殖器官的转移(而没有影响到氮素的转移),但并没影响到最终种子中的磷素含量。
综上所述,生长素转运蛋白基因OsPIN2超表达不仅能够影响水稻的株型(株高、分蘖角度、分蘖数目等)和根系的生长发育,而且还能够调节水稻磷素营养的吸收转运和分配,这些研究结果为挖掘具有相对理想株型、发展磷高效水稻新品种的育种技术提供一些研究线索。
The plant hormone auxin (indole-3-acetic acid, IAA) is an essential regulator in many plant developmental processes, including apical dominance, phototropism, gravitropism, root patterning and other physiological processes. Polar transport of auxin is essential for the establishment and maintenance of polar growth and morphological patterning. At the cellular level, the directional transport of auxin results from the asymmetric distribution of different auxin membrane carriers, including the influx carrier AUX1protein family and the efflux-facilitating PIN-FORMED (PIN) family. PINs perform a rate-limiting role in catalyzing the efflux of auxin from cells, and their asymmetric cellular localization determines the direction of cell-to-cell flow which is central to auxin-regulated growth processes.
Phosphorus (P) is an essential macronutrient for plant growth and development. Due to inorganic fixation and formation of organic complexes, as well as the slow rate of diffusion in soil, P is one of the least available plant nutrients worldwide. Plants have evolved several strategies to improve P acquisition, especially alterations in root morphology. Recent evidence has shown that auxin participate in the control of root responses to low phosphorus availability. Furthermore, auxin also has effects on the nutrients absorption, transport and distribution within plant. But there are few reports on the physiological and molecular mechanisms of the interactions between mineral nutritions and auxin.
The rice(Oryza sativa L.) genome contains12putative PIN genes encoding auxin efflux transporters, including four PIN1genes (named OsPIN1α-1d), OsPIN2, three PIN5genes (OsPIN5α-c), OsPIN8and three monocot-specific PIN genes(OsPIN9, OsPIN10α and OsPIN10b). By over-expression of OsPIN2, the only rice homologue of AtPIN2, through the transgenic approach in rice, we analysis its function in regulating rice architecture, root morphology and phosphorus nutrition. The main results were summarized as follows:
1.OsPIN2is localized on chromosome6. Sequence alignment between genomic and cDNA sequences showed that OsPIN2has7exons and6introns. The deduced amino acid sequence of OsPIN2suggests that OsPIN2is a typical intergrating membrane protein with two lyophobic domains and a big hydrophilic loop between them. Subcellular localization analysis by OsPIN2::GFP fusion protein in rice protoplast cells conformed it is localized in the cell plasma membrane.
2. Over-expression of OsPIN2significantly increased tiller angle and numbers and decreased height of the rice in comparison with WT. At the ripening stage, the0.vPIN2-over-expressing plants showed shorter panicle length, less number of grains per panicle and lower grain weight per panicle in comparison with the control.
3. Free IAA in various organs of the transgenic and WT plants was quantified by high-performance liquid chromatography (HPLC) and visualized by DR5::GUS. In the first and second leaves from the top, transgenic plants contained lower free IAA than that in the control plants. In the sheath of the first leaf, the transgenic plants and WT had nearly the same concentration of free IAA, while in the sheath of the second leaf, transgenic plants had lower free IAA concentration than that in WT. In contrast, in the root-shoot junction (shoot base) and roots, the two transgenic lines contained more free IAA than that in WT. In addition, localized external NPA application at the root-shoot junction had little effects on the root growth of the O.sPIN2-over-expression plants, which demonstrated that OsPIN2affected the polar auxin transport directly.
4. Transcriptional analyses have demonstrated that OsPIN2regulated OsLazyl, but not OsTAC1and OsPIN1b in rice, suggesting that OsPIN2has a distinct role, along with OsPIN1b and OsTAC1in the auxin-regulated growth of the leaf canopy.
5. The changes in root system architecture (RSA) triggered by phosphate (P) deprivation were studied in rice. Low P availability increased the length of root, lateral roots and the number of adventitious roots. Most effects of low P on RSA were dramatically modified in the transgenic plants or NPA treated wild-type plants. This shows that auxin plays a major role in the P starvation-induced changes of root development.
6. At seedling stage, the P concentration in the roots of transgenic plants was higher than that in WT. By contrasting the P concentration in different parts of WT and transgenic plants at the grain-filling and ripe stage, we found0sPIN2was also involved in P translocation from vegetative organs to reproductive organs in rice. But the physiological and molecular mechanism underlying the interation between auxin and phosphorus nutrition needs to be further investigated.
Taken together,OsPIN2not only has effects on the rice architecture and root growth, but also plays an important role in phosphorus utilization. Our results provide theoretical and material foundation for breeding new rice varieties with ideal-plant architecture and efficient phosphorus utilization.
引文
鲍士旦.(1999)土壤农化分析.中国农业出版社.
段俊,田长恩,梁承邺,黄毓文,刘鸿先.(1999)水稻结实过程中穗不同部位谷粒中内源激素的动态变化.植物学报41：75-79.
郭丽琢,张福锁,李春俭.(2002)打顶对烟草生长、钾素吸收及其分配的影响.应用生态学报13：819-822.
廖红,严小龙.(2000)菜豆根构型对低磷胁迫的适应性变化及基因型差异.植物学报42：158-163.
李海波,夏铭,吴平.(2001)低磷胁迫对水稻苗期侧根生长及养分吸收的影响.植物学报43：1154-1160.
陆景陵.(2003)植物营养学.中国农业大学出版社.
林兆松,郑文赞,宋银官,林永盛.(1963)水稻不同发育阶段对磷秦的吸收、运运和分配.放射性同位素及辐射的应用6：477-479.
方立魁,桑贤春,何光华.(2008)水稻分蘖角度遗传机理的研究进展.分子植物育种6：935-940.
方进,翟文学,王文明,李素文,朱立煌.(2001)转基因水稻T-DNA侧翼序列的扩增与分析.遗传学报28：345-351.
康文启,欧阳由男,董成琼等.(2007)水稻动态株型模式及其指标探讨.中国稻米1：1-6.
高洁,姜明松,李广贤,陈峰,袁守江.(2009)水稻分蘖角度的研究进展.山东农业科学7：31-34.
毛丽君,林位夫.(2008)植物生长素在农业中的应用.河北农业科学12：80-84.
倪为民,陈晓亚,许智宏,薛红卫.(2000)生长素极性运输研究进展.植物学报42：221-228.
潘瑞炽.(2004)植物生理学北京：高等教育出版社.
孙淑斌,李宝珍,胡江,徐国华.(2006)水稻低丰度表达基因OsAMT1;3实时荧光定量PCR方法的建立及其应用.中国水稻科学20：8-12.
王建林,徐正进,魏树和.(2000)水稻株型育种生理生态特性的研究现状与展望.辽宁农业科学4：23-27.
王丰,程方民.(2003)植物激素与水稻产量的关系及其在生产上的应用.现代化农业291：20-21.
王育花,赵森,陈芬,肖国樱.(2007)利用实时荧光定量PCR法检测转基因水稻外源基因拷贝数的研究.生命科学研究11：301-305.
袁隆平.(1997)杂交水稻超高产育种.杂交水稻12：1-4.
余传元,刘裕强,江玲,王春明,翟虎渠,万建民.(2005)水稻分蘖角度的QTL定位和主效基因的遗传分析.遗传学报32：948-954.
郑宪滨,曹一平,张福锁等.(2000)不同供钾水平下烤烟体内钾的循环、累积和分配.植物营养与 肥料学报6：166-172.
Abe K., Takahashi H. and Suge H. (1996) Lazy gene (la) responsible for both an agravitropism of seedlings and lazy habit of tiller growth in rice (Oryza sativa L). J. Plant. Res.109:381-386.
Ai PH, Sun SB, Zhao JN, Fan XR, Xin WJ, Guo Q, Yu L, Shen QR, Wu P, Miller AJ, et al. (2009) Two rice phosphate transporters, OsPhtl;2 and OsPht1;6, have different functions and kinetic properties in uptake and translocation. Plant J.57:798-809.
Aloni R. (1995) The induction of vascular tissues by auxin and cytokinin. In:Davies PJ, editor. Plant hormones:physiology, biochemistry and molecular biology,2nd ed. Dordrecht:Kluwer Academic Publishers.531-546.
Aloni R, Feigenbaum P, Kalev N, Rozovsky S. (2000) Hormonal control of vascular differentiation in plants:the physiological basis of cambium ontogeny and xylem evolution. In:Savidge RA, Barnett JR, Napir R, editors. Cell and molecular biology of wood formation. Oxford:BIOS Scientific Publishers.223-236.
Aloni R (2001) Foliar and axial aspects of vascular differentiation-hypotheses and evidence. J Plant Growth Regul.20:22-34
A1-Ghazi Y, Muller B, Pinloche S, Tranbarger TJ, Nacry P, Rossignol M, Tardieu F, Doumas P. (2003) Temporal response of Arabidopsis root architecture to phosphate starvation:evidence for the involvement of auxin signalling. Plant Cell Environ.26:1053-1066.
Baker DA. (2000) Long-distance vascular transport of endogenous hormones in plants and their role in source:sink regulation. Israel J. Plant Sci.48:199-203.
Baluskap F, Samaj J, Menzel D. (2003) Polar transport of auxin:carrier-mediated flux across the plasma membrane or neurotransmitter-like secretion? Trends Cell Bio.13:282-284.
Bandurski R, Cohen J, Slovin J, and Reinecke D (1995) Auxin biosynthesis and metabolism, in Plant Hormones:Physiology, Biochemistry and Molecular Biology, Davies PJ, Editor, Kluwer Academic Publishers:Dordrecht, Boston, London. ISBN 0-7923-2984-8.39-65.
Bates TR and Lynch JP. (1996) Stimulation of root hair elongation in Arabidopsis thaliana by low phosphorus availability. Plant Cell Environ.19:529-538.
Bates TR and Lynch JP. (2000a) Plant growth and phosphorus accumulation of wild type and two root hair mutants of Arabidopsis thaliana (Brassicaceae). Amer. J. Bot.87:958-963.
Bates TR and Lynch JP. (2000) The efficiency of Arabidopsis thaliana (Brassicaceae) root hairs in phosphorus acquisition. Amer. J. Bot.87:964-970.
Batten GD, Wardlaw IF. (1987) Senescence and grain development in wheat plants grown with contrasting phosphorus regimes. Aust J Plant Physiol.14:253-265.
Benjamins R, Quint A, Weijers D, Hooykaas P, Offringa R. (2001) The PINOID protein kinase regulates organ development in Arabidopsis by enhancing polar auxin transport. Development 128: 4057-4067.
Benkova E, Michniewicz M, Sauer M, Teichmann T, Seifertova D, Jurgens G and Friml J. (2003) Local, efflux-dependent auxin gradients as a common module for plant organ formation. Cell 115: 591-602.
Bennett MJ, Marchant A, Green HG, May ST, Ward SP, Millner PA, Walker AR, Schulz B, Feldmann KA. (1996) Arabidopsis AUX1 gene:a permease-like regulator of root gravitropism. Nature 273: 948-950.
Bennett MJ, Marchant A, May ST, Swarup R. (1998) Going the distance with auxin unraveling the molecular basis of auxin transport. Phil.Trans. R. Soc. Lond. B 353:1511-1515.
Benkova E, Michniewicz M, Sauer M, Teichmann T, Seifertova D, Jurgens G, Friml J. (2003) Local, Efflux-Dependent Auxin Gradients as a Common Module for Plant Organ Formation. Cell 115: 591-602.
Bernasconi P. (1996) Effect of synthetic and natural protein tyrosine kinase inhibitors on auxin efflux in zucchini (Cucurbita pepo L.) hypocotyls. Physiol. Plantarum 96:205-210.
Bhalerao RP, Eklof J, Ljung K, Marchant A, Bennett M, Sandberg G. (2002) Shoot-derived auxin is essential for early lateral root emergence in Arabidopsis seedlings. Plant J.29:325-332.
Blakeslee JJ, Bandyopadhyay A, Peer WA, Makam SN, Murphy AS (2004) Relocalization of the PIN1 auxin efflux facilitator plays a role in phototropic responses. Plant Physiol.134:28-31.
Blilou I, Xu J, Wildwater M, Willemsen V, Paponov I, Friml J, Heidstra R, Aida M, Palme K, Scheres B. (2005) The PIN auxin efflux facilitator network controls growth and patterning in Arabidopsis roots. Nature 433:39-44.
Bonser AM, Lynch J, Snapp S (1996). Effect of phosphorus deficiency on growth angle of basal roots in Phaseolus vulgaris. New Phytol.132:281-288.
Borch K, Bouma T, Brown K, Lynch JP. (1998) Interactions of ethylete and phosphorus nutrition on root growth. Flores HE, Lynth JP, Eissenstat D. Radical Biology:Advances and Perspectives on the Function of Plant Roots. Maryland:Ameriean Socity of Plant Physiologists.391-393.
Brown DE, Rashotte AM, Murphy AS, Tague BW, Peer WA, Taiz L, Muday GK (2001) Flavonoids act as negative regulators of auxin transport in vivo in Arabidopsis thaliana. Plant Physiol.126: 524-535.
Bucher M, Rausch C, Daram P. (2001) Molecular and biochemical mechanisms of phosphorus uptake into plants. J. Plant Nutr. Soil Sci.164:209-217.
Butler JH, Hu S, Brady SR, Dixon MW, Muday GK. (1998) In vitro and in vivo evidence for actin association of the naphthylphthalanic acid-binding protein from zucchini hypocotyls. Plant J.13: 291-301.
Cambridge AP, Morris DA. (1996) Transfer of exogenous auxin from the phloem to the polar auxin transport pathway in pea (Pisum sativum L.). Planta 199:583-588.
Carland FM, McHale NA. (1996) LOP1:a gene involved in auxin transport and vascular patterning in Arabidopsis. Development 122:1811-1819.
Casimiro I, Marchant A, Bhalerao RP, Beeckman T, Dhooge S, Swarup R, Graham N, Inze D, Sandberg G, Casero PL, Bennett M. (2001) Auxin transport promotes Arabidopsis lateral root initiation. Plant Cell 13:843-852.
Chandler JW. (2009) Local auxin production:a small contribution to a big field. BioEssays 31:60-70.
Chen R, Hilson P, Sedbrook J, Rosen E, Caspar T, Masson PH. (1998) The Arabidopsis thaliana AGRAVITROPIC1 gene encodes a component of polar auxin-transport efflux carrier. Proc. Natl. Acad. Sci. USA 95:5112-15117.
Chen R, Guan C, Boonsirichai K, Masson PH. (2002) Complex physiological and molecular processes underlying root gravitropism. Plant Mol. Biol.49:305-317.
Cheng YF, Dai XH and Zhao YD. (2006) Auxin biosynthesis by the YUCCA flavin monooxygenases controls the formation of floral organs and vascular tissues in Arabidopsis. Gene. Dev.20: 1790-1799.
Chiou TJ and Lin SI. (2011) Signaling Network in Sensing Phosphate Availability in Plants. Annu. Rev. Plant Biol.62:185-206.
Cho M, Lee SH, Cho HT. (2007) P-Glycoprotein4 displays auxin efflux t ransporter like action in Arabidopsis root hair cells and tobacco cells. Plant Cell 19:3930-3943.
Christensen SK, Dagenais N, Chory J, Weigel D. (2000) Regulation of auxin response by the protein kinase PINOID. Cell 100:469-478.
Cooke TJ, Racusen RH, Cohen JD. (1993) The role of auxin in plant embryogenesis. Plant Cell 5: 1494-1495.
Cooper HD, Clarkson DT. (1989) Cycling of amino nitrogen and other nutrients between shoots and roots in cereals-a possible mechanism integrating shoot and root in the regulation of nutrient uptake. J. Exp. Bot.40:753-762.
Davies CR, Wareing PF. (1965) Auxin-directed transport of radiophosphorus in stems. Planta 65: 139-156.
Davies PJ, Mithchell EK. (1972) Transport of Indoleacctic Acid in Intact Roots of Phaseolus coccinens. Planta 105:139-154.
Davies PJ, Rubery PH. (1978) Components of auxin transport in stem segments of Pisum sativum L. Planta 142:211-219.
Delbarre A, Muller P, Imhoff V, Guern J. (1996) Comparison of mechanisms controlling uptake and accumulation of 2,4-dichlorophenoxyacetic acid, naphthalene-1-acetic acid, and indole-3-acetic acid in suspension-cultured tobacco cells. Planta 198:532-541.
Delker C, Raschke A, Quint M. (2008) Auxin dynamics:the dazzling complexity of a small molecule's message. Planta 227:929-941.
Dharmasiri S, Swarup R, Mockaitis K, Dharmasiri N, Singh SK, Kowalchyk M, Marchant A, Mills S, Sandberg G, Bennett MJ, Estelle M. (2006) AXR4 is required for localization of the auxin influx facilitator AUX1. Science 312:1218-1220.
Ding JY, Jia JW, Yang LT et al. (2004) Validation of a rice specific gene, sucrose phosphate synthase, used as the endogenous reference gene for qualitative and real-time quantitative PCR detection of transgenes. J. Agr. Food Chem.52:3372-3377.
Eiichi T. (2005) Regulation of root growth by plant hormones-roles for auxin and gibberelin. Crit. Rev. Plant Sci.24:249-265.
Eric MK and Malcolm JB. (2006) Auxin transport:a field in flux. Trends Plant Sci.11:382-386.
Fan XR, Jia LJ, Li YL, Smith SJ, Miller AJ, Shen QR. (2007) Comparing nitrate storage and remobilization in two rice cultivars that differ in their nitrogen use efficiency. J. Exp. Bot.58: 1729-1740.
Farquharson KL. (2008) Phosphate-Deprived Roots Are Hypersensitive to Auxin. Plant Cell 20:3183.
Faulkner IJ, Rubery PH (1992) Flavonoids and flavonoid sulphates as probes of auxin-transport regulation in Cucurbita pepo hypocotyl segments and vesicles. Planta 186:618-625.
Feraru E, Friml J. (2008) PIN Polar Targeting. Plant Physiol.147:1553-1559.
Fisher C, Neuhaus G (1996) Influence of auxin on the establishment of bilateral symmetry in monocots. Plant J.9:659-669.
Forestan C, Meda S, Varotto S. (2010) ZmPIN1-Mediated Auxin Transport Is Related to Cellular Differentiation during Maize Embryogenesis and Endosperm Development. Plant Physiol.152: 1373-1390.
Forestan C, Farinati S, Varotto S. (2012) The maize PIN gene family of auxin transporters. Front. Plant Sci.6:1-23.
Friml J, Palme K. (2002) Polar auxin transport-old questions and new concepts? Plant Mol. Biol.49: 273-284.
Friml J, Benkova E, Blilou I, Wishniewska J, Hamann T, Ljung K, Woody S, Sandberg G, Scheres B, J rgens G. (2002a) AtPIN4 mediates sink-driven auxin gradients and root patterning in Arabidopsis. Cell 108:61-673.
Friml J, Wisniewska J, Benkova E, Mendgen K, Palme K. (2002b) Lateral relocationof auxin efflux regulator PIN3 mediates tropism in Arabidopsis. Nature 415:806-809.
Friml J. (2003) Auxin transport-shaping the plant. Curr. Opin. Plant Biology 6:7-12.
Friml J, Vieten A, Sauer M, Weijers D, Schwarz H, Hamann T, Offringa R and Jurgens G. (2003) Efflux-dependent auxin gradients establish the apical-basal axis of Arabidopsis. Nature 426:47-53.
Friml J, Yang X, Michniewicz M, Weijers D, Quint A, Tietz O, Benjamins R, Ouwerkerk P, Ljung K, Sandberg G. (2004) A PINOID-dependent binary switch in apical-basal PIN polar targeting directs auxin efflux. Science 306:862-865.
Friml J, Grunewald W. (2010) The march of the PINs:developmental plasticity by dynamic polar targeting in plant cells. EMBO J.29:2700-2714.
Fujino K, Matsuda Y, Ozawa K, Nishimura T, Koshiba T, Fraaije MW, Sekiguchi H. (2008) NARROW LEAF 7 controls leaf shape mediated by auxin in rice. Mol. Genet. Genomics 279:499-507.
Gahoonia TS and Nielsen NE. (1998) Direct evidence on participation of root hairs in phosphorus (32P) uptake from soil. Plant soil.198:147-152.
Galweiler L, Guan C, Muller A, Wisman E, Mendgen K, Yephremov A, Palme K. (1998) Regulation of polar auxin transport by AtPIN1 in Arabidopsis vascular tissue. Science 282:2226-2230.
Garcia O, Bouige P, Forestier C, Dassa E. (2004) Inventory and comparative analysis of rice and Arabidopsis ATP-binding cassette (ABC) systems. J. Mol. Biol.343:249-265.
Ge L, Chen H, Jiang JF, Zhao Y, Xu ML, Xu YY, Tan KH, Xu ZH, Chong K. (2004) Overexpression of OsRAA1 Causes Pleiotropic Phenotypes in Transgenic Rice Plants, including Altered Leaf, Flower, and Root Development and Root Response to Gravity. Plant Physiol.135:1502-1513.
Gehring CA, Irving HR, Parish RW. (1990) Effects of auxin and abscisic acid on cytosolic calcium and pH in plant cells. Proc. Nati. Acad. Sci. USA 87:9645-9649.
Geisler M, Blakeslee JJ, Bouchard R, et al. (2005) Cellular efflux of auxin catalyzed by the Arabi dopsis MDR/PGP transporter AtPGP1. Plant J.44:179-194.
Geldner N, Friml J, Stierhof YD, Jurgens G, Palme K. (2001) Auxin transport inhibitors block cycling and vesicle trafficking. Nature 413:425-428.
Geldner N, Anders N, Wolters H, Keicher J, Kornberger W, Muller P, Delbarre A, Ueda T, Nakano A, Jurgens G. (2003) The Arabidopsis GNOM ARF-GEF mediates endosomal recycling, auxin transport, and auxin-dependent plant growth. Cell 112:219-230.
Gil P, Dewey E, Friml J, Zhao Y, Snowden KC, Putterill J, Palme K, Estelle M, Chory J. (2001) BIG:a calossin-like protein required for polar auxin transport in Arabidopsis. Genes Dev.15:1985-1997.
Gilbert GA, Knight JD, Vance CP, Allan DL. (2000) Proteoid root development of phosphorus deficient lupin is mimicked by auxin and phosphonate. Ann. Bot. (Lond) 85:921-928.
Goldsmith, MHM. (1977) The polar transport of auxin. Annu. Rev. Plant Physiol.28:439-478.
Grebe M, Friml J, Swarup R, Ljung K, Sandberg G, Terlou M, Palme K, Bennett MJ, Scheres B. (2002) Cell Polarity Signaling in Arabidopsis Involves a BFA-Sensitive Auxin Influx Pathway. Curr. Biol. 12:329-334.
Grierson C, Schiefelbein J. (2002) Root Hairs.The Arabidopsis Book. Roekville, MD:Ameriean Society of Plant Biologists.
Guo B, Jin Y, Wussler C, Blancaflor EB, Motes CM, VersawWK. (2008) Functional analysis of the Arabidopsis PHT4 family of intracellular phosphate transporters. New Phytol.177:889-898.
Hagen G, Guilfoyle T (2002) Auxin-responsive gene expression:genes, promoters and regulatory factors. Plant Mol. Biol.49:373-385
Hammond JP, Bennett MJ, Bowen HC. (2003) Change in gene expression in Arabidopsis shoots during phosphate starvation and the potential for developing smart plants. Plant Physiol.132:578-596.
Hertel R, Lomax TL, Briggs WR. (1983) Auxin transport in membrane vesicles from Cucurbita pepo L. Planta 157:193-201.
Hoyerova K, Perry L, Hand P, Lankova M, Kocabek T, May S, Kottova J, Paces J, Napier R, Zazimalova E. (2008) Functional Characterization of PaLAX1, a Putative Auxin Permease, in Heterologous Plant Systems. Plant Physiol.146:1128-1141.
Imsande J, Touraine B. (1994) N demand and the regulation of nitrate uptake. Plant Physoil.105:3-7.
Jaworski EG (1971) Nitrate reductase assay in intact plant tissues. Bioehem. Biophys. Res. Commun.43: 1274-1279.
Jacobs M, Rubery PH. (1988) Natrurally occurring auxin transport regulators. Science 241:346-349.
Jasinski M, Ducos E, Martinoia E, Boutry M. (2003) The ATP-binding cassette transporters:structure, function, and gene family comparison between rice and Arabidopsis. Plant Physiol.131: 1169-1177.
Jia HF, Ren HY, Gu M, Zhao JN, Sun SB, Zhang X, Chen JY, Wu P, Xu GH (2011) The phosphate transporter gene OsPht1;8 is involved in phosphate homeostasis in Rice. Plant Physiol.156: 1164-1175.
Jin J, Huang W, Gao JP, Yang J, Shi M, Zhu MZ, Luo D and Lin HX. (2008) Genetic control of rice plant architecture under domestication. Nat. Genet.40:1365-1369.
Johnson JF, Allan DL, Vance CP (1994). Phosphorus stress-induced proteoid roots show altered metabolism in Lupinus albus. Plant Physiol.104:657-665.
Johnson JF, Vance CP, Allan DL. (1996) Phosphorus deficiency in Lupinus albus. Altered lateral root development and enhanced expression of phosphoenolpyruvate carboxylase. Plant Physiol.112: 31-41.
Jungk A, Seeling B and Gerke J. (1993) Mobilization of different phosphate fractions in the rhizosphere. Plant Soil 156:91-94.
Karandashov V, Bucher M. (2005) Symbiotic phosphate transport in arbuscular mycorrhizas. Trends Plant Sci.10:22-29.
Kiss JZ, Wright JB, Caspar T. (1996) Gravitropism in roots of intermediate-starch mutants of Arabidopsis. Plant Physiol.97:237-244.
Klee HJ, Horsch RB, Hinchee MA, Hein MB, Hoffmann MB (1987) The effects of overproduction of two Agrobacterium tumefaciens T-DNA auxin biosynthetic gene products in transgenic petunia plants. Gene Dev.1:86-96.
Koizumi K, Sugiyama M, Fukuda H. (2000) A series of novel mutants of Arabidopsis thaliana that are defective in the formation of continuous vascular network:Calling the auxin signal flow canalization hypothesis into question. Development 127:3197-3204.
Kramer EM, Bennett MJ. (2006) Auxin transport:a field in flux. Trends Plant Sci.11:382-386.
Lau S, Jurgens G, Smet ID. (2008) The Evolving Complexity of the Auxin Pathway. Plant Cell 20: 1738-1746.
Li P, Wang Y, Qian Q, Fu Z, Wang M, Zeng D, Li B, Wang X and Li J. (2007) LAZY1 controls rice shoot gravitropism through regulating polar auxin transport. Cell Res.17:402-410.
Lin WY, Lin SI, Chiou TJ. (2009) Molecular regulators of phosphate homeostasis in plants. J. Exp. Bot. 60:1427-1438.
Liu CM, Xu ZH, Chua NH. (1993) Auxin Polar transport is essential for the establishment of bilateral symmetry during early plant embryo genesis. Plant Cell 5:621-630.
Liu F, Wang ZY, Ren HY, Shen C, Li Y, Ling HQ,Wu CY, Lian XM, Wu P (2010) OsSPX1 suppresses the function of OsPHR2 in the regulation of expression of OsPT2 and phosphate homeostasis in shoots of rice. Plant J.62:508-517.
Liu YG, Robert FW. (1995a) Thermal asymmetric interlaced PCR:Automatable amplification and sequencing of inset and fragments from PI and YAC clones for chromosome walking. Genomics 25: 674-681.
Liu YG, Norihiro M, Teruko O, Robert FW. (1995b) Efficient isolation and mapping of Arabidopsis thaliana T-DNA inset junctions by thermal asymmetric interlaced PCR. Plant J.8:457-463.
Ljung K, Ostin A, Lioussanne L, Sandberg G. (2001) Developmental regulation of indole-3-acetic acid turnover in scots pine seedlings. Plant Physiol.125:464-475.
Ljung K, Hull AK, Kowalczyk M, March ant A, Celenza J, Cohen JD,Sandberg G (2002) Biosynthesis, conjugation, catabolism and homeostasis of indole-3-acetic acid in Arabidopsis thaliana. Plant Mol. Biol.50:309-332.
Lomax TL, Mehlhorn RJ, Briggs WR. (1985) Active Auxin Uptake by Zucchini Membarne Vesicles: Quantitation Using ESR Volume and △pH Determinations. Proc. Natl. Acad. Sci. USA 82: 6541-6545.
Lomax TL and Hieks GR. (1992) Specific auxin-binding proteins in the plasma membrane:Receptors or transporters? Biochem. Soc. Trans.20:64-69.
Lomax TL, Muday K, Rubery PH. (1995) Auxin transport. Davies PJ. Plant Hormones.2nd. Dordrecht: Kluwer Academic Publishers 509-530.
Lopez-Bucio J, Hernandez-Abreu E, Sanchez-Calderon L, Nieto-Jacobo MF, Simpson J, Herrera-Estrella L. (2002) Phosphate availability alters architecture and causes changes in hormone sensitivity in the Arabidopsis root system. Plant Physiol.129:244-256.
Lopez-Bucio, Cruz-Ramirez A, Herrera-Estrella L. (2003) The role of nutrient availability in regulating root architecture. Curr. Opin. Plant Biol.6:280-287.
Lu YL, Xu YC, Shen QR and Dong CX. (2008) Effects of different nitrogen forms on the growth and cytokinin content in xylem sap of tomato (Lycopersicon esculentum Mill.) seedlings. Plant Soil 315: 67-77.
Luschnig C, Gaxiola RA, Grisafi P, Fink GR. (1998) EIR1, a root-specific protein involved in auxin transport, is required for gravitropism in Arabidopsis thaliana. Genes Dev.12:2175-2187.
Luschnig, C. (2001) Auxin transport:why plants like to think BIG. Curr. Biol.11:831-833.
Luschnig C. (2002) Auxin transport:ABC proteins join the club. Trends Plant Sci.7:329-332.
Lynch JP and Brown KM. (1997) Ethylene and plant responses to nutritional stress. Physiol. Plantarum 100:613-619.
Ma Z, Walk TC, Marcus A. (2001) Morphological synergism in root hair length, density, initiation and geometry for phosphorus acquisition in Arabidopsis thaliana:A modeling approach. Plant Soil 236: 221-235.
Marchant A, Kargul J, May ST, Muller P, Delbarre A, Perrot-Rechenmann C, Bennett MJ. (1999) AUX1 regulates root gravitropism in Arabidopsis by facilitating uptake within root apical tissues. EMBO J 18:2066-2073.
Marschner H. (1995) Mineral Nutrition of Higher Plants. London:Academic Press.
Marschner H, Kirkby EA, Engels C. (1997) Importance of cycling and recycling of mineral nutrients within plants for growth and development.Bot. Acta.110:265-273.
Masutomo K, Akira S, Hitoshi S, Nobutaka T. (1989) Fluctuation of endougenous IAA level in rice during its life cycle. Agric Biol Chem 53:1089-1094.
Masucci JD, Schiefelbein JW. (1994) The rhd6 Mutation of Arabidopsis thaliana Alters Root-Hair Initiation through an Auxin-and Ethylene-Associated Proeess. Plant Physiol.106:1335-1346.
Mattsson J, Sung ZR, Berleth T. (1999) Responses of plant vascular systems to auxin transport inhibition. Development 126:2979-2991.
Mattsson J, Ckurshumova W, Berleth T. (2003) Auxin signaling in Arabidopsis leaf vascular development. Plant Physiol.131:1327-1339.
Meijer AH, Scarpella E, van Dijk EL, Qin L, Taal AJC, Rueb S, Harrington SE, McCouch SR, Schilperoort RA, Hoge JHC. (1997) Transcriptional repression by Oshoxl, a novel homeodomain Ieucine zipper protein from rice. Plant J.11:263-276.
Michniewicz M, Brewer PB, Friml J. (2007) Polar auxin transport and asymmetric auxin distribution. American Society of Plant Biologists:The Arabidopsis Book.
Mimura T. (1995) Homeostasis and transport of inorganic phosphate in plants. Plant Cell Physiol.36: 1-7.
Mitchell EK and Davies PJ. (1975) Evidence for three different systems of movement of indoleacetic acid in intact roots of haseolus coccineus. Plant Physiol.33:290-294.
Morris DA. (1982) Hormonal regulation of sink invertase activity:Implications for the control of assimilate partioning. In:Wareing P F, ed. Plant Growth Substances. London:Academic Press, 659-668.
Morris DA, Robinson JS. (1998) Targeting of auxin carriers to theplasma membrane:effect of monensin on transmembrane auxin transport in Cucurbita pepo L. tissue. Planta 193:194-202.
Morris DA, Rubery PH, Jarman J, Sabater M. (1991) Effects of inhibitors of protein synthesis on transmembrane auxin transport in Cucurbita pepo L. hypocotyl segments. J. Exp. Bot.42:773-783.
Morris DA. (2000) Transmembrane auxin carrier system:Dynamic regulators of Polar auxin transport. Plant Growth Regul.32:161-172.
Muday GK and Haworth P. (1994) Tomato root growth, gravitropism, and lateral development: correlation with auxin transport. Plant Physiol. Biochem.32:193-203.
Muday GK and DeLong A. (2001) Polar auxin transport:controlling where and how much. Trends Plant Sci.6:535-542.
Muday GK and Murphy AS. (2002) An Emerging Model of Auxin Transport Regulation. Plant Cell 14: 293-299.
Muller A, Guan C, Galweiler L, Tanzler P, Huijser P, Marchant A, Parry G, Bennett M, Wisman E, Palme K. (1998) AtPIN2 defines a locus of Arabidopsis for root gravitropism control. EMBO J 17: 6903-6911.
Murphy A, Peer WA, Taiz L. (2000) Regulation of auxin transport by aminopeptidases and endogenous flavonoids. Planta 211:315-324.
Nagashima A, Uehara Y and Sakai T. (2008) The ABC subfamily B auxin transporter AtABCB19 is involved in the inhibitory effects of N-1-naphthyphthalamic acid on the phototropic and gravitropic responses of Arabidopsis hypocotyls. Plant Cell Physiol.49:1-250.
Nacry P, Canivenc G, Muller B, Azmi A, Onckelen HV, Rossignol M, Doumas P. (2005) A role for auxin distribution in the responses of the root system architeture to phosphat starvation in Arabidopsis. Plant Physiol.138:2061-2074.
Ni WM, Chen XY, Xu ZH, Xue HW. (2002) Isolation and functional analysis of a Brassica juncea gene encoding a component of auxin efflux carrier. Cell Res.12:235-245.
Noh B, Murphy AS, Spalding EP. (2001) Multidrug resistance-like genes of Arabidopsis required for auxin transport and auxin-mediated development. Plant Cell 13:2441-2454.
Nonhebel HM, Cooney TP, Simpson R. (1993) The route control and compartmentation of auxin synthesis. Aust. J Plant Physiol.20:527-539.
Normanl YJ, Sovin JP, Cohen JD. (2004) Auxin metabolism in plant hormones:Biosynthesis, signal transduction, action! In:Davies PJ (ed) Plant hormones:biosynthesis, signal transduction, action. Dordrecht:Kluwer Academic Publisher 36-62.
Okada K, Ueda J, Komaki MK, Bell CJ, Shimura Y. (1991) Requirement of the Auxin Polar Transport System in Early Stages of Arabidopsis Floral Bud Formation. Plant Cell 3:677-684.
Ottenschlager I, Wolff P, Wolverton C, Bhalerao RP, Sandberg G, Ishikawa H, Evans M, Palme K. (2003) Gravity-regulated differential auxin transport from columella to lateral root cap cells. Proc. Natl. Acad. Sci. USA 100:2987-2991.
Palme K, Galweiler L. (1999) PIN-Pointing the molecular basis of auxin transport. Curr. Opin. Plant Biol.2:375-381.
Palme K, Dovzhenko A, Ditengou FA. (2006) Auxin transport and gravitational research:perspectives. Protoplasma 229:175-181.
Paponov IA, Teale WD, Trebar M, Blilou I, Palme K. (2005) The PIN auxin efflux facilitators: Evolutionary and functional perspectives. Trends Plant Sci.10:170-177.
Parry G, Delbarre A, Marchant A, Swarup R, Napier R, Perrot-Rechenmann C, Bennett, MJ. (2001) Novel auxin transport inhibitors phenocopy t he auxin influx carrier mutation auxl. Plant J.25: 399-406.
Paszkowski U, Kroken S, Roux C, Briggs SP. (2002) Rice phosphate transporters include an evolutionarily divergent gene specifically activated in arbuscular mycorrhizal symbiosis. Proc. Natl. Acad. Sci. USA 99:13324-13329.
Patrick JW, Steains KH. (1987) Auxin-promoted transport metabolites in stems of Phaseolus vulgaris L.: Auxin dose-response curves and effects of inhibitors of polar auxin transport. J. Exp. Bot.38: 203-210.
Peer WA, Murphy AS, Brown DE, Tague BW, Muday GK, Taiz L (2001) Flavonoid accumulation patterns of transparent testa mutants of Arabidopsis. Plant Physiol.126:536-548.
Peer WA, Bandyopadhyay A, Blakeslee JJ, Makam SN, Chen RJ, Masson PH, Murphy AS. (2004) Variation in expression and protein localization of the PIN family of auxin efflux facilitator proteins in fiavonoid mutants with altered auxin transport in Arabiodopsis thaliana. Plant Cell 16: 1898-1911.
Peer WA, Blakeslee JJ, Yang HB, Murphy AS. (2011) Seven Things We Think We Know about Auxin Transport. Mol. Plant 4:1-18.
Peng SB, Khush GS, Cassman KG (1994) Evolution of the new plant ideo type for increased yield potential. In:Cassman KG, ed. Breaking the yield barrier. IRRI, Philippines.5-21.
P6rez-Torres C, Lopez-Bucio J, Cruz-Ramirez A, Ibarra-Laclette E, Dharmasiri S, Estelle M, Herrera-Estrellab L. (2008) Phosphate availability alters lateral root development in Arabidopsis by modulating auxin sensitivity via a mechanism involving the TIR1 auxin receptor. Plant Cell 20: 3258-3272.
Petrasek J, Mravec J, Bouchard R, Blakeslee JJ, Abas M, Seifertova D, Wisniewska J, Tadele Z, Kubes M, Covanova M, Dhonukshe P, Skupa P, Benkova E, Perry L, Krecek P, Lee OK, Fink GR, Geisler M, Murphy AS, Luschnig C, Zazimalova E, Friml J. (2006) PIN Proteins Perform a Rate-Limiting Function in Cellular Auxin Efflux. Science 312:914-918.
Phillips IJD. (1968) Nitrogen, Phosphorus, and Potassium Distribution in Relation to Apical Dominance in Dwarf Bean(Phaseolus vulgaris, c.v. Canadian Wonder). J Exp. Bot.19:617-627.
Poirier Y, Bucher M. (2002) Phosphate transport and homeostasis in Arabidopsis. Washington D.C.: American Society of Plant Biologists PP:1-35.
Raghothama KG. (2000) Phosphate transport and signaling. Curr. Opin. Plant Biol.3:182-187.
Raghothama KG. Katthikeyan AS. (2005) Phosphate acquisition. Plant Soil 274:37-49.
Rahman A, Hosokawa S, OonoY, AmakawaT, Goto N, Tsurumi S. (2002) Auxin and ethylene response interaetions during Arabidopsis root hair development dissected by auxin influx modulators.PIant Physio.1130:1908-1917.
Rashotte AM, Brady SR, Reed RC, Ante SJ, Muday GK. (2000) Basipetal Auxin Transport Is Required for Gravitropism in Roots of Arabidopsis. Plant Physiol.122:481-490.
Rashotte AM, DeLong A, Muday GK. (2001) Genetic and chemical reductions in protein phosphatase activity alter auxin transport, gravity response, and lateral root growth. Plant Cell 13:1683-1697.
Rausch C, Bucher M. (2002) Molecular mechanisms of phosphate transport in plants. Planta,16:23-37.
Romano CP, Hein MB, Klee HJ. (1991) Inactivation of auxin in tobacco transformed with the indoleacetic acid-lysine synthetase gene of Pseudomonas savastanoi. Genes Dev.5:438-446.
Rubery PH and Sheldrake AR. (1974) Carrier-mediated auxin transport. Planta 118:101-121.
Rubery PH. (1987) Auxin transport. In:Davies, PJ ed. Plant hormoenes. Dordrecht Martinus Nijhoff Publishers 341-362.
Rubery PH. (1990) Phytotropins:receptors and endogenous ligands. Symp. Soc. Exp. Biol.44:119-46.
Rubio V, Bustos R, Irigoyen ML, Cardona-Lopez X, Rojas-Triana M, Paz-Ares J. (2009) Plant hormones and nutrient signaling. Plant Mol. Biol.69:361-373.
Ruegger M, Dewey E, Hobbie L, Brown D, Bernasconip, Turner J, Muday G, Estelle M. (1997) Reduced naphthylphthalamic acid binding in the tir3 mutant of Arabidopsis is associated with a reduction in polar auxin transport and diverse morphological defects. Plant Cell 9:745-757.
Sabatini S, Beis D, Wolkenfelt H, Murfett J, Guilfoyle T, Malamy J, Benfy P, Leyser O, Bechtold N, Weisbeek P, Scheres B. (1999) An auxin-dependent distal organizer of pattern and polarity in the Arabidopsis root. Cell 99:463-472.
Sambrook J, Divid R.2001. Molecular Cloning:Alaboratry Manual (Ⅲ), Cold Spring Harbor Lab (CSHL) Press.
Sanchez-Fernandez R, Davies TG, Coleman JO, Rea PA. (2001) The Arabidopsis thaliana ABC protein superfamily, a complete inventory. J. Biol. Chem.276:30231-30244.
Slovin JP, Bandurski RS, Cohen JD (1999) Auxin, in Biochemistry and Molecular Biology of Plant Hormone, P Hooykaas, M Hall, and K Libbenga, Editors, Elsevier Science:Oxford.115-140.
Santelia D, Vincenzetti V, Azzarello E, et al. (2005) MDR-like ABC transporter AtPGP4 is involved in auxin-mediated lateral root and root hair development. FEBS Lett.579:5399-5406.
Scarpella E, Rueb S, Boot KJM, Hoge JHC, Meijer AH. (2000) A role for the rice homeobox gene Oshoxl in provascular cell fate commitment. Development 127:3655-3669.
Scarpella E, Boot KJ, Rueb S, Meijer AH. (2002) The procambium specification gene Oshoxl promotes polar auxin transport capacity and reduces its sensitivity toward inhibition. Plant Physiol.130: 1349-1360.
Schnabel EL, Frugoli J. (2004) The PIN and LAX families of auxin transport genes in Medicago truncatula. Mol. Genet. Genomics 272:420-432.
Schrader J, Baba K, May ST, Palme K, Bennett M, Bhalerao RP, Sandberg G (2003) Polar auxin transport in the wood-forming tissues of hybrid aspen is under simultaneous control of developmental and environmental signals. Proc. Natl. Acad. Sci. USA 100:10096-100101.
Shen JB, Yuan LX, Zhang JL, Li HG, Bai ZH, Chen XP, Zhang WF and Zhang FS. (2011) Phosphorus Dynamics:From Soil to Plant. Plant Physiol.156:997-1005.
Sieburth LE. (1999) Auxin Is Required for Leaf Vein Pattern in Arabidopsis. Plant Physio.121: 1179-1190.
Skene KR, James WM. (2000) A comparison of the effects of auxin on cluster root initiation and development in Grevillea robusta Cunn. Ex R. Br. (Proteaceae) and the genus Lupinus (Leguminosae). Plant Soil 219:221-229.
Smith SE, Barker SJ. (2002) Plant phosphate transporter genes help harness the nutritional benefits of arbuscular mycorrhizal symbiosis. Trends Plant Sci.7:189-190.
Steinmann T, Geldner N, Grebe M, Mangold S, Jackson CL, Paris S, Glweiler L, Palme K, Jurgens G (1999) Coordinated polar localization of auxin efflux carrier PIN1 by GNOM ARF GEF. Science 286:316-318.
Sun HG and Zhang FS. (2000) Growth response of wheat roots to phosphorus defieieney. Acta Bor Sin. 42:913-919.
Sun SB, Gu M, Cao Y, Huang XP, Zhang X, Ai PH, Zhao JN, Fan XR, Xu GH. (2012) A constitutive expressed phosphate transporter, OsPhtl;1, modulates phosphate uptake and translocation in Pi-replete rice. Plant Physiol.159:112-120.
Swarup K, Benkova E, Swarup R, Casimiro I, Peret B, Yang Y et al. (2008) The auxin influx carrier LAX3 promotes lateral root emergence. Nature Cell Bio.10:946-954.
Swarup R, Friml J, Marchant A, Ljung K, Sandberg G, Palme K, Bennett M. (2001) Localization of the auxin permease AUX1 suggests two functionally distinct hormone transport pathways operate in the Arabidopsis root apex. Genes Dev.15:2648-2653.
Swarup R, Kramer EM, Perry P, Knox K, Leyser HMO, Haseloff J, Beemster GTS, Bhalerao R, Bennett MJ. (2005) Root gravitropism requires lateral root cap and epidermal cells for transport and response to a mobile auxin signal. Nat. Cell Biol.7:1057-1065.
Tan LB, Li XR, Liu FX, et al. (2008) Control of a key transition from prostrate to erect growth in rice domestication. Nat. Genet.40:1360-13641.
Tanaka H, Dhonukshe P, Brewer PB, Friml J (2006) Spatiotemporal asymmetric auxin distribution:a means to coordinate plant development. Cell Mol. Life Sci.63:2738-2754.
Tasaka M, Kato T. (1999) The endodermis and shoot gravitropism. Elsevier Sci.4:103-107.
Teale WD, Paponov IA, Palme K. (2006) Auxin in action:signalling, transport and the control of plant growth and development. Nature reviews 7:847-859.
Terasaka K, Blakeslee JJ, Titapiwatanakun B, et al. (2005) PGP4, an ATP binding cassette Pglycoprotein, catalyzes auxin transport in Arabidopsis thaliana roots. Plant Cell 17:2922-2939.
Theodoru ME, Plaxton WC. (1993) Metabolic adaptations of plant respiration to nutritional phosphate deprivation. Plant Physiol.101:339-344.
Thomas TH. (1986) Hormonal control of assimilate movement and compartmentation. In:Bopp M, ed. Plant Growth Substances. Berlin:Springer-Verlag,350-359.
Ticconi CA, Abel S. (2004) Short on phosphate:plant surveillance and countermeasures. Trends Plant Sci.9:548-55.
Titapiwatanakun B and Murphy AS. (2008) Post-transcriptional regulation of auxin transport proteins: cellular trafficking, protein phosphorylation, protein maturation, ubiquitination, and membrane composition. J Exp. Bot.29:1-15.
Tobena-Santamaria R, Bliek M, Ljung K,Sandberg G. Mol JNM, Souer E, and Koes R. (2002) FLOOZY of petunia is a flavin mono-oxygenase-like protein required for the specification of leaf and flower architecture. Genes Dev.16:753-763
Torrey JG (1976) Root hormones and plant growth. An. Rev. Plant Physiol.27:435-459.
Tsurumi S and Ohwaki Y. (1978) Transport of 14C-labeled indoleacetic acid in Vicia root segments. Plant Cell Physiol.19:1195-1206.
Ulmasov T, Murfett J, Hagen G and Guilfoyle TJ. (1997) Aux/IAAproteins repress expression of reporter genes containing natural and highly active synthetic auxin response elements. Plant Cell 9: 1963-1971.
Utsuno K, Shikanai T, Yamada Y, Hashimoto T. (1998) AGR, an Agravitropic Locus of Arabidopsis thaliana, Encodes a Novel Membrane-Protein Family Member. Plant CellPhysiol.39:1111-1118.
Vance CP, Uhde SC, Allan DL. (2003) Phosphorus acquisition and use:critical adaptations by plants for securing a nonrenewable resource. New Phytol.157:423-447.
Wang X, Zhang W, Huang Y, and Li S. (2004) Modeling and simulation of point-non-point source effluent trading in Taihu Lake area:Perspective of non-point sources control in China. Sci. Total Environ.325:39-50.
Wang JR, Hu H, Wang GH, Li J, Chen JY, Wu P. (2009) Expression of PIN Genes in Rice (Oryza sativa L.):tissue specificity and regulation by hormones. Mol. Plant 2:823-831.
Went FW. (1974) Reflections and speculations. Annu. Rev. Plant Physiol.25:1-26.
Wildman SG. (1997) The auxin-A, B enigma:scientific fraud or scientific ineptitude? Plant Growth Reg. 22:37-68.
Williamson LC, Ribrioux SP, Fitter AH, Leyser HM. (2001). Phosphate availability regulates root system architecture in Arabidopsis. Plant Physiol.126:875-882.
Wisniewska J, Xu J, Seifertova D, Brewer PB, Ruzicka K, Blilou I, Rouquie D,Benkova E, Scheres B, Friml J. (2006) Polar PIN Localization Directs Auxin Flow in Plants. Science 312:883.
Woo YM, Park HJ, Su'udi M, Yang JI, Park JJ, Back K, Park YM, An G. (2007) Constitutively wilted 1, a member of the rice YUCCA gene family, is required for maintaining water homeostasis and an appropriate root to shoot ratio. Plant Mol. Biol.65:125-136.
Woodward AW and Bartel B. (2005) Auxin:Regulation, Action, and Interaction. Ann. Bot.95:707-735.
Xu M, Zhu L, Shou HX, Wu P. (2005) A PIN1 family gene, OsPIN1, involved in auxin-dependent adventitious root emergence and tillering in rice. Plant Cell Physiol.46:1674-1681.
Xu Y, Mccouch SR and Shen Z. (1998) Transgressive segregation of tiller angle in rice caused by complementary gene action. Crop Sci.38:12-19.
Yang YD, Hammes UZ, Taylor CG, Schachtman DP, Nielsen E. (2006) High-Affinity Auxin Transport by the AUX1 Influx Carrier Protein. Curr. Bio.16:1123-1127.
Yang H, Murphy AS. (2009) Functional expression and characterization of Arabidopsis ABCB, AUX1 and PIN auxin transporters in Schizosaccharomyces pombe. Plant J.59:179-191.
Yamamoto M, Yamamoto KT. (1998) Differential effects of 1-naphthaleneacetic acid, indole-3-acetic acid and 2,4-dichlorophenoxyacetic acid on the gravitropic response of roots on an auxin-resistant mutant of Arabidopsis, auxl. Plant Cell Physiol.39:660-664.
Yamamoto Y, Kamiya N, Morinaka Y, Matsuoka M, Sazuka T. (2007) Auxin biosynthesis by the YUCCA genes in rice. Plant Physiol.143:1362-1371.
Yoshihara T, and lino M. (2007) Identification of the gravitropism-related rice gene LAZY1 and elucidation of LAZY 1-dependent and independent gravity signaling pathways. Plant Cell Physiol. 48:678-688
Young LM, Evans ML, Hertel R. (1990) Correlations between gravitropic curvature and auxin movement across gravistimulated roots of Zea mays. Plant Physiol.92:792-796.
Yu B, Lin Z, Li H, Li X, Li J, Wang Y, Zhang X, Zhu Z, Zhai W, Wang X, Xie D and Sun C. (2007) TAC1, a major quantitative trait locus controlling tiller angle in rice. Plant J.52:891-898.
Zazimalova E, Krecek P, Skupa P, Hoyerova K and Petrasek J. (2007) Polar transport of the plant hormone auxin-the role of PIN-FORMED (PIN) proteins. Cell. Mol. Life Sci.64:1621-1637.
Zhang J, Nodzynski T, Pencik A, Rolcik J and Friml J. (2010) PIN phosphorylation is sufficient to mediate PIN polarity and direct auxin transport. Proc. Natl. Acad. Sci. USA.107:918-922.
Zhao YD, Christensen SK, Fankhauser C, Cashman JR, Cohen JD, Weigel D, Chory J.(2001) A Role for Flavin Monooxygenase-Like Enzymes in Auxin Biosynthesis. Science 291:306-309.
Zhou DX, Yin K, Xu ZH, Xue HW. (2003) Effect of Polar Auxin Transport on Rice Root Development. Acta Botanica Sinica 45:1421-1427.
