Martin MaryAnn, Newton Irene L G
Department of Biology, Indiana University, Bloomington, IN USA.
bioRxiv. 2023 Feb 27:2023.02.26.530160. doi: 10.1101/2023.02.26.530160.
The most common intracellular bacterial infection is a microbe that manipulates host reproduction and is used in control of insect vectors. Phenotypes induced by have been studied for decades and range from sperm-egg incompatibility to male killing. How alters host biology is less well understood. Previously, we characterized the first effector - WalE1, which encodes a synuclein domain at the N terminus. Purified WalE1 sediments with and bundles actin and when heterologously expressed in flies, increases titer in the developing oocyte. In this work, we first identify the native expression WalE1 by infecting both fly cells and whole animals. WalE1 appears as aggregates, separate from cells. We next show that WalE1 co-immunoprecipitates with the host protein Past1 and that WalE1 manipulates host endocytosis. Yeast expressing WalE1 show deficiency in uptake of FM4-64 dye, and flies harboring mutations in or overexpressing WalE1 are sensitive to AgNO, a hallmark of endocytosis defects. Finally, we also show that null flies harbor more overall and in late egg chambers. Our results identify interactions between a secreted effector and a host protein and point to yet another important host cell process impinged upon by
最常见的细胞内细菌感染是一种操纵宿主繁殖并用于控制昆虫媒介的微生物。由其诱导的表型已被研究数十年，范围从精卵不相容到雄性致死。关于它如何改变宿主生物学的了解较少。此前，我们鉴定了首个效应蛋白——WalE1，其在N端编码一个突触核蛋白结构域。纯化的WalE1与肌动蛋白一起沉淀并使其成束，当在果蝇中异源表达时，会增加发育中卵母细胞中的滴度。在这项工作中，我们首先通过感染果蝇细胞和整个动物来鉴定WalE1的天然表达。WalE1表现为聚集体，与细胞分离。接下来，我们表明WalE1与宿主蛋白Past1共免疫沉淀，并且WalE1操纵宿主内吞作用。表达WalE1的酵母在摄取FM4-64染料方面表现出缺陷，并且在相关基因中携带突变或过表达WalE1的果蝇对硝酸银敏感，这是内吞作用缺陷的一个标志。最后，我们还表明相关基因缺失的果蝇总体上以及在晚期卵室中携带更多的（相关微生物）。我们的结果确定了一种分泌的效应蛋白与宿主蛋白之间的相互作用，并指出了另一个受其影响的重要宿主细胞过程
