Benabdillah Rachid, Mota Luís Jaime, Lützelschwab Silke, Demoinet Emilie, Cornelis Guy R
Microbial Pathogenesis Unit, Christian de Duve Institute of Cellular Pathology and Université catholique de Louvain, B1200 Brussels, Belgium.
Microb Pathog. 2004 May;36(5):247-61. doi: 10.1016/j.micpath.2003.12.006.
YopM is a type III secretion effector from Yersinia which contributes to pathogenicity but whose action still remains unclear. It is an acidic, leucine-rich repeats (LRR) containing protein which migrates to the nucleus of target cells in spite of the fact that it does not contain any classical nuclear localization signal (NLS). Using a yeast approach, we observed that the three first LRRs (LRR1-3) and the 32 C-terminal residues of YopM (YopMC-ter) act as NLSs in yeast. Furthermore, by transfection of HEK293T cells, we observed that YopMC-ter could direct large recombinant EGFP-LexA-AD proteins into the nucleus of mammalian cells confirming that it contains a NLS. Critical residues for nuclear targeting were identified by site-directed mutagenesis in YopMC-ter. In addition, we show that YopMC-ter NLS is crucial for the nuclear targeting of an EGFP-YopM fusion protein.
YopM是耶尔森氏菌的一种III型分泌效应蛋白，它对致病性有影响，但其作用仍不清楚。它是一种富含亮氨酸重复序列（LRR）的酸性蛋白，尽管它不包含任何经典的核定位信号（NLS），但仍能迁移到靶细胞的细胞核中。通过酵母实验方法，我们观察到YopM的前三个LRR（LRR1 - 3）和YopM的32个C末端残基（YopMC-ter）在酵母中起到核定位信号的作用。此外，通过转染HEK293T细胞，我们观察到YopMC-ter能够将大型重组EGFP-LexA-AD蛋白导入哺乳动物细胞的细胞核，证实它含有一个核定位信号。通过对YopMC-ter进行定点诱变确定了核靶向的关键残基。此外，我们表明YopMC-ter核定位信号对于EGFP-YopM融合蛋白的核靶向至关重要。
