THE REGULATION OF ALPHA(5)BETA(1) INTEGRIN EXPRESSION IN HUMAN MUSCLE-CELLS
THE REGULATION OF ALPHA(5)BETA(1) INTEGRIN EXPRESSION IN HUMAN MUSCLE-CELLS
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DOI：
10.1006/dbio.1994.1217
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发表时间：
1994-08-01
影响因子：
2.7
通讯作者：
HOLLAND, PC
中科院分区：
文献类型：
--
作者：
BLASCHUK, KL;HOLLAND, PC
我们检测了α (5) β(1)整合素在克隆或荧光激活的来源于人二头肌的卫星细胞中的表达。去除血清和肌肉细胞生长和增殖所需的因子都诱导了末端分化，并导致编码α(5)和β(1)整合素亚基的mRNA转录物的协同下调。α(5)亚基的相应下调发生在蛋白质水平。5-溴-2'-脱氧尿苷（BUdR）是一种抑制肌肉细胞分化的胸腺嘧啶类似物，用BUdR处理培养物可导致α(5)整合素亚基mRNA和蛋白水平的表达增加。然而，从budr处理的培养物中去除血清和生长因子后，α(5)亚基信息和蛋白质的水平仍然显著下调，这表明在肌肉形成过程中α (5) β(1)整合素的下调不是肌肉细胞末梢分化所必需的，也不是肌肉细胞末梢分化的结果。在补充了血清和生长因子的培养基中维持细胞可以防止α(5)整合素亚基表达的下调，尽管这种培养基中没有单一的确定成分可以单独阻止α(5)整合素亚基表达的下调。总之，这些结果表明，α (5) β(1)整合素表达的下调并不是肌肉细胞终末分化的结果，而是依赖于肌肉细胞生长和增殖所必需的外源性生长因子的组合。(C) 1994学术出版社，Inc.
The expression of alpha(5) beta(1) integrin was examined in either cloned or fluorescence-activated cell-sorted satellite cells derived from human biceps muscle. Removal of serum and factors required for muscle cell growth and proliferation both induced terminal differentiation and resulted in a coordinate downregulation of mRNA transcripts encoding alpha(5) and beta(1) integrin subunits. A corresponding downregulation of the alpha(5) subunit occurred at the protein level. Treatment of cultures with 5-bromo-2'-deoxyuridine (BUdR), a thymidine analog which inhibits muscle cell differentiation, resulted in increased expression of alpha(5) integrin subunit at both the mRNA and protein levels. However, levels of alpha(5) subunit message and protein were still markedly downregulated on removal of serum and growth factors from BUdR-treated cultures, indicating that downregulation of alpha(5) beta(1) integrin during myogenesis does not require and is not a consequence of muscle cell terminal differentiation. Downregulation of alpha(5) integrin subunit expression could be prevented by maintenance of cells in medium supplemented with serum and growth factors, although no single defined component of this medium could on its own prevent the downregulation of alpha(5) integrin subunit expression. Collectively, these results suggest that downregulation of alpha(5) beta(1) integrin expression is not a consequence of muscle cell terminal differentiation, but is dependent on a combination of exogenous growth factors which are also required for muscle cell growth and proliferation. (C) 1994 Academic Press, Inc.