Abstract：
Endocytic dynamins self-assemble into helical scaffolds and utilize energy from GTP hydrolysis to constrict and sever tubular membranous necks of budded endocytic intermediates. They bind the membrane using a pleckstrin-homology domain (PHD). The PHD is characterized by four unstructured loops, two of which partially insert into the membrane. Recent studies reveal that loop insertion lowers the bending rigidity of the membrane and that mutations in these two loops produce separable and opposite effects on the efficiency of dynamin-catalyzed membrane fission. Here, we review the current understanding of dynamin-catalyzed membrane fission and attempt to reconcile contrasting notions that have emerged from biochemical and cellular studies evaluating the role of the PHD in this process. We propose that two membrane-inserting loops act as \"gears\" that define the catalytic efficiency of the dynamin helical scaffold in membrane fission.
摘要：
内吞动力自组装成螺旋支架，并利用GTP水解产生的能量收缩和切断出芽内吞中间体的管状膜颈。它们使用pleckstrin同源结构域(PHD)结合膜。PHD的特点是四个非结构化回路，其中两个部分插入膜。最近的研究表明，环路插入会降低膜的弯曲刚度，并且这两个环路中的突变会对动态蛋白催化的膜裂变效率产生可分离且相反的影响。这里,我们回顾了目前对动力蛋白催化的膜裂变的理解,并试图调和从评估PHD在这一过程中的作用的生化和细胞研究中出现的不同观点.我们建议两个膜插入环充当“齿轮”，定义膜裂变中动态蛋白螺旋支架的催化效率。
