A fast fiber enhancer exists in the muscle regulatory factor 4 gene promoter

详细信息    查看全文

• 作者：Pin ; Christopher L. ; Konieczny ; Stephen F.
• 关键词：MyoD ; Myf-5 ; Myogenin ; MRF4 ; Transcription ; Myogenesis
• 刊名：Biochemical and Biophysical Research Communications
• 出版年：2002
• 出版时间：November 22, 2002
• 年：2002
• 卷：299
• 期：1
• 页码：7-13
• 全文大小：282 K

文摘

The development of skeletal muscle is a highly regulated process governed by the four myogenic regulatory factors (MRFs) MyoD, myf-5, myogenin, and MRF4. While these factors exhibit some unique functions, part of their individual activity can be attributed to different temporal and spatial expression patterns. To delineate the factors that control expression of the MRFs, we have begun a molecular dissection of the MRF4 gene promoter. Through the generation of promoter/reporter gene constructs, we show that an 853bp fragment, residing 4kb upstream of the MRF4 transcriptional start site (853AV), is able to enhance expression of the basal MRF4 promoter 3–4-fold in myogenic cell cultures. Analysis of the 853AV enhancer in transgenic mice indicates that this region drives MRF4 gene expression primarily in fast muscle fibers, suggesting that the normal adult MRF4 expression pattern is regulated by a variety of control elements that may dictate fiber-type specificity.