کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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2177195 | 1094627 | 2007 | 15 صفحه PDF | دانلود رایگان |
SummaryOrganization of actin filaments into a well-organized sarcomere structure is critical for muscle development and function. However, it is not completely understood how sarcomeric actin/thin filaments attain their stereotyped lengths. In an RNAi screen in Drosophila primary muscle cells, we identified a gene, sarcomere length short (sals), which encodes an actin-binding, WH2 domain-containing protein, required for proper sarcomere size. When sals is knocked down by RNAi, primary muscles display thin myofibrils with shortened sarcomeres and increased sarcomere number. Both loss- and gain-of-function analyses indicate that SALS may influence sarcomere lengths by promoting thin-filament lengthening from pointed ends. Furthermore, the complex localization of SALS and other sarcomeric proteins in myofibrils reveals that the full length of thin filaments is achieved in a two-step process, and that SALS is required for the second elongation phase, most likely because it antagonizes the pointed-end capping protein Tropomodulin.
Journal: - Volume 13, Issue 6, 4 December 2007, Pages 828–842