Galactomutarotase and Other Galactose-Related Genes Are Rapidly Induced by Retinoic Acid in Human Myeloid Cells

详细信息    查看全文

• 作者：Tongkun Pai ; Qiuyan Chen ; Yao Zhang ; Reza Zolfaghari ; A. Catharine Ross
• 刊名：Biochemistry
• 出版年：2007
• 出版时间：December 25, 2007
• 年：2007
• 卷：46
• 期：51
• 页码：15198 - 15207
• 全文大小：296K
• 年卷期：v.46,no.51(December 25, 2007)
• ISSN：1520-4995

文摘

Aldose-1-epimerase (mutarotase) catalyzes the interconversion of and hexoses, which isessential for normal carbohydrate metabolism and the production of complex oligosaccharides. Galactosemutarotase (GALM) has been well characterized at the protein level, but information is lacking on theregulation of GALM gene expression. We report herein that all-trans-retinoic acid (RA), an activemetabolite of vitamin A that is known to induce myeloid lineage cell differentiation into macrophage-likecells, induces a rapid and robust regulation of GALM mRNA expression in human myeloid cells. all-trans-RA at a physiological concentration (20 nM), or Am580, a ligand selective for the nuclear retinoidreceptor RAR, increased GALM mRNA in THP-1 cells, with significantly increased expression in 2 h,increasing further to an ~8-fold elevation after 6-40 h (P < 0.005). In contrast, tumor necrosis factor-did not increase GALM mRNA expression, although it is capable of inducing cell differentiation. RAalso increased GALM mRNA in U937 and HL-60 cells. The increase in GALM mRNA by RA wasblocked by pretreating THP-1 cells with actinomycin D but not by cycloheximide. GALM protein andmutarotase activity were also increased time dependently in RA-treated THP-1 cells. In addition to GALM,several other genes in the biosynthetic pathway of galactosyl-containing complex oligosaccharides weremore highly expressed in RA-treated THP-1 cells, including B4GALT5, ST3GAL3, ST6GALNAC5, andGALNAC4S-6ST. Thus, the results of this study identify RA as a significant regulator of GALM andother galactose-related genes in myeloid-monocytic cells, which could affect energy utilization and synthesisof cell-surface glycoproteins or glycolipids involved in cell motility, adhesion, and/or functional properties.