Laboratory of Pathogen Host Interactions (LPHI), CNRS, University of Montpellier, Montpellier, France; email:
Annu Rev Microbiol. 2022 Sep 8;76:619-640. doi: 10.1146/annurev-micro-041320-021425. Epub 2022 Jun 7.
Apicomplexa are obligatory intracellular parasites that sense and actively invade host cells. Invasion is a conserved process that relies on the timely and spatially controlled exocytosis of unique specialized secretory organelles termed micronemes and rhoptries. Microneme exocytosis starts first and likely controls the intricate mechanism of rhoptry secretion. To assemble the invasion machinery, micronemal proteins-associated with the surface of the parasite-interact and form complexes with rhoptry proteins, which in turn are targeted into the host cell. This review covers the molecular advances regarding microneme and rhoptry exocytosis and focuses on how the proteins discharged from these two compartments work in synergy to drive a successful invasion event. Particular emphasis is given to the structure and molecular components of the rhoptry secretion apparatus, and to the current conceptual framework of rhoptry exocytosis that may constitute an unconventional eukaryotic secretory machinery closely related to the one described in ciliates.
顶复门生物是专性细胞内寄生虫，能够感应并主动侵入宿主细胞。入侵是一个保守的过程，依赖于独特的专门分泌细胞器微线体和棒状体的时间和空间控制的外排。微线体的外排首先发生，并且可能控制着棒状体分泌的复杂机制。为了组装入侵机制，与寄生虫表面相关的微线体蛋白与棒状体蛋白相互作用并形成复合物，这些复合物反过来又被靶向进入宿主细胞。本综述涵盖了关于微线体和棒状体外排的分子进展，并重点介绍了这两个隔室中排出的蛋白质如何协同工作以驱动成功的入侵事件。特别强调了棒状体分泌装置的结构和分子成分，以及棒状体外排的当前概念框架，该框架可能构成一种非常规的真核分泌机制，与纤毛描述的机制密切相关。
