Institute of Integrative and Comparative Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK.
Eur J Cell Biol. 2010 Jun;89(6):437-48. doi: 10.1016/j.ejcb.2009.11.027. Epub 2010 Mar 11.
A screen was instigated to identify novel protein components of the Caenorhabditis elegans sarcomere. The subcellular localisation of full-length GFP fusion proteins was examined, in transgenic animals, for 62 essentially uncharacterized genes thought to be expressed within bodywall muscle cells. Three genes, T03G6.3, C46G7.2 and K04A8.6, were identified for further study. K04A8.6::GFP only displayed a regular sarcomeric distribution sporadically. However, C46G7.2::GFP localised to the centre of A-bands and dense bodies and T03G6.3::GFP localised in the I-band, of the bodywall muscle sarcomeres, consistently. This success with such a small screen suggests that there are further minor components of the C. elegans sarcomere yet to be discovered. Fluorescence Recovery After Photobleaching (FRAP) was applied to live transgenic individuals to assess the mobility of T03G6.3 and C46G7.2 and other well-known constituents of the sarcomere in vivo. Proteins associated with the thin filaments showed dynamic exchange whilst those associated with thick filaments appeared more static. This is the first demonstration that there are sarcomeric proteins in C. elegans muscle cells in dynamic exchange and that the rates of exchange in vivo correspond in general terms with observations in other experimental systems.
一个屏幕被启动，以鉴定秀丽隐杆线虫肌节的新型蛋白质成分。在转基因动物中，对 62 个基本未被描述的、被认为在体壁肌肉细胞中表达的基因的全长 GFP 融合蛋白的亚细胞定位进行了检测。有三个基因，T03G6.3、C46G7.2 和 K04A8.6，被确定进一步研究。K04A8.6::GFP 仅偶尔显示规则的肌节分布。然而，C46G7.2::GFP 定位于 A 带和致密体的中心，而 T03G6.3::GFP 定位于体壁肌肉肌节的 I 带，始终如此。如此小的屏幕取得的成功表明，线虫肌节的其他次要成分仍有待发现。荧光恢复后光漂白（FRAP）被应用于活的转基因个体，以评估 T03G6.3 和 C46G7.2 以及肌节中其他已知成分在体内的流动性。与细肌丝相关的蛋白质显示出动态交换，而与粗肌丝相关的蛋白质则显得更静态。这是第一个证明线虫肌肉细胞中有肌节蛋白在进行动态交换的证据，并且体内的交换速度与其他实验系统中的观察结果大致相符。
