کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5532943 1402089 2017 17 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Multimodal and Polymorphic Interactions between Anillin and Actin: Their Implications for Cytokinesis
ترجمه فارسی عنوان
تعاملات چندجملهای و پلیمورفیک بین آنیلین و اکتین: پیامدهای آن برای سیتوکینز
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی بیولوژی سلول
چکیده انگلیسی


- The actin-binding domain (ActBD) of anillin is required for faithful cytokinesis.
- The ActBD of Drosophila anillin harbors three discernable actin-binding sites.
- Binding of two of the three sites to F-actin is mutually exclusive.
- F-actin bundled by the ActBD can adopt two distinct morphologies.
- The ActBD is necessary and sufficient for actin bundling and cortical localization.

Cytokinesis of animal cells requires the assembly of a contractile ring, which promotes daughter cell splitting. Anillin is a conserved scaffold protein involved in organizing the structural components of the contractile ring including filamentous actin (F-actin), myosin, and septins and in forming the subsequent midbody ring. Like other metazoan homologs, Drosophila anillin contains a conserved domain that can bind and bundle F-actin, but the importance and molecular details of its interaction with F-actin remain unclear. Here, we show that in a depletion-and-rescue assay in Drosophila S2 cells, anillin lacking the entire actin-binding domain (ActBD) exhibits defective cortical localization during mitosis and a greatly diminished ability to support cytokinesis. Using in vitro binding assays and electron microscopy on recombinant fragments, we determine that the anillin ActBD harbors three distinct actin-binding sites (ABS 1-3). We show that each ABS binds to a distinct place on F-actin. Importantly, ABS1 and ABS3 partially overlap on the surface of actin and, therefore, interact with F-actin in a mutually exclusive fashion. Although ABS2 and ABS3 are sufficient for bundling, ABS1 contributes to the overall F-actin bundling activity of anillin and enables anillin to switch between two actin-bundling morphologies and promote the formation of three-dimensional F-actin bundles. Finally, we show that in live S2 cells, ABS2 and ABS3 are each required and together sufficient for the robust cortical localization of the ActBD during cytokinesis. Collectively, our structural, biochemical, and cell biological data suggest that multiple anillin-actin interaction modes promote the faithful progression of cytokinesis.

Graphical Abstract145

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Biology - Volume 429, Issue 5, 10 March 2017, Pages 715-731
نویسندگان
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