Development transitions of thin filament proteins in rat extraocular muscles.
Development transitions of thin filament proteins in rat extraocular muscles.
复制标题
大鼠眼外肌细丝蛋白的发育转变。
DOI：
10.1016/j.yexcr.2012.11.010
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发表时间：
2013
影响因子：
3.7
通讯作者：
Andrade,FranciscoH
中科院分区：
文献类型：
--
作者：
Moncman,CaroleL;Andrade,MiguelE;McCool,AndreaA;McMullen,ColleenA;Andrade,FranciscoH
眼外肌是横纹肌的一个独特的子集。在出生后的发育过程中，眼外肌经历了许多肌球蛋白亚型的转变，发生在出生后第10天（P10）和P15之间。其中包括：（1）胚胎肌球蛋白从球层丢失，导致其表达仅限于眶层;（2）眼外肌球蛋白和假定的强直肌球蛋白（myh 7 b/14）开始表达;（3）非肌肉肌球蛋白IIB从肌膜下位置重新分布到球层慢纤维中的肌节分布。在这项研究中，我们研究了出生后的外观和分布的α-辅肌动蛋白，原肌球蛋白和星云蛋白亚型在出生后发育的大鼠眼外肌。虽然肌节α-辅肌动蛋白在出生时就可以检测到，但α-辅肌动蛋白3在P15左右出现。原肌球蛋白-1和原肌球蛋白-2从出生起就以与成年动物相同的分布存在。通过凝胶电泳和蛋白质印迹法监测nebulin的表达。在P5-10，星云蛋白表现出较低的分子量比观察到的P15，后来在出生后发育。P10和P15之间α-辅肌动蛋白3和星云蛋白表达的变化与上文详述的肌球蛋白亚型的转变一致。这些数据表明，P10-P15是眼外肌成熟的关键时期，与眼睑张开一致。
Extraocular muscles are a unique subset of striated muscles. During postnatal development, the extraocular muscles undergo a number of myosin isoform transitions that occur between postnatal day P10 (P10) and P15. These include: (1) loss of embryonic myosin from the global layer resulting in the expression restricted to the orbital layer; (2) the onset of expression of extraocular myosin and the putative tonic myosin (myh 7b/14); and (3) the redistribution of nonmuscle myosin IIB from a subsarcolemmal position to a sarcomeric distribution in the slow fibers of the global layer. For this study, we examined the postnatal appearance and distribution of α-actinin, tropomyosin, and nebulin isoforms during postnatal development of the rat extraocular muscles. Although sarcomeric α-actinin is detectable from birth, α-actinin 3 appears around P15. Both tropomyosin-1 and -2 are present from birth in the same distribution as in the adult animal. The expression of nebulin was monitored by gel electrophoresis and western blots. At P5-10, nebulin exhibits a lower molecular mass than observed P15 and later during postnatal development. The changes in α-actinin 3 and nebulin expression between P10 and P15 coincide with transitions in myosin isoforms as detailed above. These data point to P10–P15 as the critical period for the maturation of the extraocular muscles, coinciding with eyelid opening.