ArlI、ArlJ和CirA参与古菌IV型菌毛介导的运动调节。
Involvement of ArlI, ArlJ, and CirA in Archaeal Type-IV Pilin-Mediated Motility Regulation.
作者信息
Chatterjee Priyanka, Garcia Marco A, Cote Jacob A, Yun Kun, Legerme Georgio P, Habib Rumi, Tripepi Manuela, Young Criston, Kulp Daniel, Dyall-Smith Mike, Pohlschroder Mecky
机构信息
University of Pennsylvania, Department of Biology, Philadelphia PA, USA.
Perelman School of Medicine, University of Pennsylvania, Philadelphia PA, USA.
出版信息
bioRxiv. 2024 Mar 20:2024.03.04.583388. doi: 10.1101/2024.03.04.583388.
Many prokaryotes use swimming motility to move toward favorable conditions and escape adverse surroundings. Regulatory mechanisms governing bacterial flagella-driven motility are well-established, however, little is yet known about the regulation underlying swimming motility propelled by the archaeal cell surface structure, the archaella. Previous research showed that deletion of the adhesion pilins (PilA1-6), subunits of the type IV pili cell surface structure, renders the model archaeon non-motile. In this study, we used EMS mutagenesis and a motility assay to identify motile suppressors of the Δ[] strain. Of the eight suppressors identified, six contain missense mutations in archaella biosynthesis genes, and . Overexpression of these and mutant constructs in the respective multi-deletion strains Δ[]Δ and Δ[]Δ confirmed their role in suppressing the Δ[] motility defect. Additionally, three suppressors harbor co-occurring disruptive missense and nonsense mutations in , a gene encoding a proposed regulatory protein. A deletion of resulted in hypermotility, while overexpression in wild-type cells led to decreased motility. Moreover, qRT-PCR analysis revealed that in wild-type cells, higher expression levels of , , and the archaellin gene were observed in motile early-log phase rod-shaped cells compared to non-motile mid-log phase disk-shaped cells. Conversely, Δ cells, which form rods during both early and mid-log phases, exhibited similar expression levels of genes in both growth phases. Our findings contribute to a deeper understanding of the mechanisms governing archaeal motility, highlighting the involvement of ArlI, ArlJ, and CirA in pilin-mediated motility regulation.
许多原核生物利用游动运动性向有利条件移动并逃离不利环境。调控细菌鞭毛驱动运动性的机制已得到充分确立,然而,对于由古菌细胞表面结构——古菌鞭毛推动的游动运动性的潜在调控机制,我们所知甚少。先前的研究表明,IV型菌毛细胞表面结构的亚基粘附菌毛蛋白(PilA1 - 6)缺失会使模式古菌失去运动能力。在本研究中,我们使用了EMS诱变和运动性测定来鉴定Δ[]菌株的运动性抑制子。在鉴定出的八个抑制子中,有六个在古菌鞭毛生物合成基因和中含有错义突变。在各自的多缺失菌株Δ[]Δ和Δ[]Δ中过表达这些和突变构建体,证实了它们在抑制Δ[]运动缺陷中的作用。此外,三个抑制子在一个编码假定调控蛋白的基因中同时存在破坏性的错义突变和无义突变。缺失会导致运动性增强,而在野生型细胞中过表达会导致运动性降低。此外,qRT-PCR分析表明,在野生型细胞中,与非运动性的对数中期盘状细胞相比,在运动性的对数早期杆状细胞中观察到、和古菌鞭毛蛋白基因的表达水平更高。相反,在对数早期和中期都形成杆状的Δ细胞在两个生长阶段中基因的表达水平相似。我们的研究结果有助于更深入地理解古菌运动性的调控机制,突出了ArlI、ArlJ和CirA在菌毛蛋白介导的运动性调控中的作用。