Spatial proteomics reveal that the protein phosphatase PTP1B interacts with and may modify tyrosine phosphorylation of the rhomboid protease RHBDL4.
J Biol Chem
; 294(30): 11486-11497, 2019 07 26.
Article
em En
| MEDLINE
| ID: mdl-31177093
ABSTRACT
Rhomboid-like proteins are evolutionarily conserved, ubiquitous polytopic membrane proteins, including the canonical rhomboid intramembrane serine proteases and also others that have lost protease activity during evolution. We still have much to learn about their cellular roles, and evidence suggests that some may have more than one function. For example, RHBDL4 (rhomboid-like protein 4) is an endoplasmic reticulum (ER)-resident protease that forms a ternary complex with ubiquitinated substrates and p97/VCP (valosin-containing protein), a major driver of ER-associated degradation (ERAD). RHBDL4 is required for ERAD of some substrates, such as the pre-T-cell receptor α chain (pTα) and has also been shown to cleave amyloid precursor protein to trigger its secretion. In another case, RHBDL4 enables the release of full-length transforming growth factor α in exosomes. Using the proximity proteomic method BioID, here we screened for proteins that interact with or are in close proximity to RHBDL4. Bioinformatics analyses revealed that BioID hits of RHBDL4 overlap with factors related to protein stress at the ER, including proteins that interact with p97/VCP. PTP1B (protein-tyrosine phosphatase nonreceptor type 1, also called PTPN1) was also identified as a potential proximity factor and interactor of RHBDL4. Analysis of RHBDL4 peptides highlighted the presence of tyrosine phosphorylation at the cytoplasmic RHBDL4 C terminus. Site-directed mutagenesis targeting these tyrosine residues revealed that their phosphorylation modifies binding of RHBDL4 to p97/VCP and Lys63-linked ubiquitinated proteins. Our work lays a critical foundation for future mechanistic studies of the roles of RHBDL4 in ERAD and other important cellular pathways.
Palavras-chave
BioID; Lys63-linked ubiquitin; PTP1B PTP1N; VCP p97; endoplasmic-reticulum-associated protein degradation (ERAD); intramembrane proteolysis; phosphoproteomics; polyubiquitin chain; proteinprotein interaction; proteostasis; rhomboid protease; rhomboid-like protein 4 (RHBDL4); tyrosine-protein phosphatase (tyrosine phosphatase)
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Tirosina
/
Proteômica
/
Proteína Tirosina Fosfatase não Receptora Tipo 1
/
Proteínas de Membrana
Tipo de estudo:
Prognostic_studies
Limite:
Humans
Idioma:
En
Revista:
J Biol Chem
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Reino Unido