Clash of the titin

杨柳

The sarcomere is more than a complicated piece of structural machinery. According to new results by McElhinny et al. (page 125), a building block of striated muscle cells called MURF-1 may also indirectly regulate gene expression.
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. A# [% d' |: s% y/ dMURF-1 localizes to sarcomeres thanks to its interaction with titin, a major structural component of the muscle sarcomere, and the largest vertebrate protein identified to date. Titin is anchored at the sarcomere Z-lines, as are thin (actin) filaments. From there it stretches across entire half sarcomeres to overlap at the mid-line (M-line), where it helps anchor thick (myosin) filaments in a central location.0 c* n2 l$ z, p1 u: J3 H
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Now McElhinny et al. show that different domains of titin perform independent functions. Disturbance of the titin–MURF-1 interaction leads to a complete disruption of M-line and thick filament structure. But the remaining titin regions can still stabilize sarcomeric thin filaments and Z-lines.
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Then there is the nuclear connection. The authors demonstrate nuclear localization of MURF-1, and interaction with a glucocorticoid-responsive transcriptional activator. Thus, titin may recognize structural alterations in the sarcomere and signal to the nucleus by releasing MURF-1 for translocation to the nucleus and transcriptional activation. A possible mechanism could involve titin phosphorylation of MURF-1, as titin's kinase domain lies adjacent to its MURF-1–binding domain.(Sarcomere thick filaments (white) are di)

lab2010

楼上的稍等啦  

sky蓝

我回不回呢 考虑再三 还是不回了吧 ^_^  

IPS干细胞

感觉好像在哪里看过了，汗~  

mk990

真是天底下好事多多  

生物小菜鸟

我在努力中  

红旗

正好你开咯这样的帖  

sky蓝

我想要`~  

昕昕

今天临床的资料更新很多呀

Whole

昨晚多几分钟的准备，今天少几小时的麻烦。