GSBS Student Publications
Title
A tyrosine-phosphorylated 12-amino-acid sequence of enteropathogenic Escherichia coli Tir binds the host adaptor protein Nck and is required for Nck localization to actin pedestals
GSBS Program
Biochemistry & Molecular Pharmacology
Publication Date
2002-03-29
UMMS Affiliation
Graduate School of Biomedical Sciences; Department of Molecular Genetics and Microbiology
Document Type
Article
Disciplines
Life Sciences | Medicine and Health Sciences
Abstract
Enteropathogenic Escherichia coli (EPEC) and enterohaemorrhagic E. coli (EHEC) each promote the reorganization of actin into filamentous pedestal structures beneath attached bacteria during colonization of the intestinal epithelium. Central to this process is the translocation of the protein Tir (translocated intimin receptor) into the plasma membrane of host cells, where it interacts with the bacterial outer membrane protein intimin and triggers cellular signalling events that lead to actin rearrangement. Actin signalling by EPEC Tir requires a tyrosine residue, Y474, which is phosphorylated in the host cell. In contrast, EHEC Tir lacks this residue and generates pedestals independently of tyrosine phosphorylation. Consistent with this difference, recent work indicates that EHEC Tir cannot functionally replace EPEC Tir. To identify the role that tyrosine phosphorylation of EPEC Tir plays in actin signalling, we generated chimeric EHEC/EPEC Tir proteins and identified a 12-residue sequence of EPEC Tir containing Y474 that confers actin-signalling capabilities to EHEC Tir when the chimera is expressed in EPEC. Nck, a mammalian adaptor protein that has been implicated in the initiation of actin signalling, binds to this sequence in a Y474 phosphorylation-dependent manner and is recruited to the pedestals of EPEC, but not of EHEC.
Source
Mol Microbiol. 2002 Mar;43(5):1227-41.
Journal/Book/Conference Title
Molecular microbiology
Related Resources
PubMed ID
11918809
Repository Citation
Campellone, Kenneth Geno; Giese, Andrew; Tipper, Donald J.; and Leong, John M., "A tyrosine-phosphorylated 12-amino-acid sequence of enteropathogenic Escherichia coli Tir binds the host adaptor protein Nck and is required for Nck localization to actin pedestals" (2002). GSBS Student Publications. 174.
https://escholarship.umassmed.edu/gsbs_sp/174