کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4361545 | 1301397 | 2008 | 9 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Bacterial Actin Assembly Requires Toca-1 to Relieve N-WASP Autoinhibition Bacterial Actin Assembly Requires Toca-1 to Relieve N-WASP Autoinhibition](/preview/png/4361545.png)
SummaryActin polymerization in the mammalian cytosol can be locally activated by mechanisms that relieve the autoinhibited state of N-WASP, an initiator of actin assembly, a process that also requires the protein Toca-1. Several pathogenic bacteria, including Shigella, exploit this host feature to infect and disseminate efficiently. The Shigella outer membrane protein IcsA recruits N-WASP, which upon activation at the bacterial surface mediates localized actin polymerization. The molecular role of Toca-1 in N-WASP activation during physiological or pathological actin assembly processes in intact mammalian cells remains unclear. We show that actin tail initiation by S. flexneri requires Toca-1 for the conversion of N-WASP from a closed inactive conformation to an open active one. While N-WASP recruitment is dependent on IcsA, Toca-1 recruitment is instead mediated by S. flexneri type III secretion effectors. Thus, S. flexneri independently hijacks two nodes of the N-WASP actin assembly pathway to initiate localized actin tail assembly.
Journal: - Volume 3, Issue 1, 17 January 2008, Pages 39–47