Castelo L, Jay D G
Department of Physiology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA.
Mol Biol Cell. 1999 May;10(5):1511-20. doi: 10.1091/mbc.10.5.1511.
Immunocytochemistry and in vitro studies have suggested that the ERM (ezrin-radixin-moesin) protein, radixin, may have a role in nerve growth cone motility. We tested the in situ role of radixin in chick dorsal root ganglion growth cones by observing the effects of its localized and acute inactivation. Microscale chromophore-assisted laser inactivation (micro-CALI) of radixin in growth cones causes a 30% reduction of lamellipodial area within the irradiated region whereas all control treatments did not affect lamellipodia. Micro-CALI of radixin targeted to the middle of the leading edge often split growth cones to form two smaller growth cones during continued forward movement (>80%). These findings suggest a critical role for radixin in growth cone lamellipodia that is similar to ezrin function in pseudopodia of transformed fibroblasts. They are consistent with radixin linking actin filaments to each other or to the membrane during motility.
免疫细胞化学和体外研究表明，ERM（埃兹蛋白-根蛋白-膜突蛋白）家族蛋白根蛋白可能在神经生长锥运动中发挥作用。我们通过观察根蛋白局部急性失活的影响，测试了其在鸡背根神经节生长锥中的原位作用。生长锥中根蛋白的微尺度发色团辅助激光失活（micro-CALI）导致照射区域内片状伪足面积减少30%，而所有对照处理均未影响片状伪足。靶向生长锥前缘中部的根蛋白micro-CALI在持续向前运动期间（>80%）常使生长锥分裂形成两个较小的生长锥。这些发现表明根蛋白在生长锥片状伪足中起关键作用，这与埃兹蛋白在转化成纤维细胞伪足中的功能相似。它们与根蛋白在运动过程中将肌动蛋白丝相互连接或与膜连接一致。
