Smith C K, Janney M J, Allen R E
Lilly Research Laboratories, Eli Lilly and Company, Greenfield, Indiana 46140.
J Cell Physiol. 1994 May;159(2):379-85. doi: 10.1002/jcp.1041590222.
The satellite cell is responsible for growth and repair of postnatal skeletal muscle. We investigated the expression of the myogenic regulatory gene (MRG) family in these cells in the stages from quiescence to fusion. Using polymerase chain reaction amplification of reverse-transcribed RNA (RT-PCR) isolated from adult rat satellite cells, we demonstrated a temporal sequence of gene activation, which is distinct from that previously observed in embryonic somatic cells. No MRG expression was detected in predominantly quiescent cells. MyoD is activated by 12 h in cell culture, prior to the first evidence of proliferation. MRF4 and myf-5 appear by 48 h and may be associated with the first division cycle. Myogenin is not detectable until 72 h after satellite cell recovery from the muscle fiber, coincidental with the first evidence of differentiation.
卫星细胞负责出生后骨骼肌的生长和修复。我们研究了从静止期到融合期的这些细胞中肌源性调节基因（MRG）家族的表达。通过对从成年大鼠卫星细胞中分离的逆转录RNA进行聚合酶链反应扩增（RT-PCR），我们证明了基因激活的时间顺序，这与先前在胚胎体细胞中观察到的不同。在主要处于静止期的细胞中未检测到MRG表达。在细胞培养12小时后，MyoD被激活，此时尚未出现增殖的首个证据。MRF4和myf-5在48小时出现，可能与第一个分裂周期有关。直到卫星细胞从肌纤维中恢复72小时后才能检测到肌细胞生成素，这与分化的首个证据同时出现。
