P62/SQSTM1 tyrosine phosphorylation LC-MS/MS
Ontology highlight
ABSTRACT:
INSTRUMENT(S):
ORGANISM(S): Homo Sapiens (human)
TISSUE(S): Permanent Cell Line Cell, Cell Culture
DISEASE(S): Disease Free
SUBMITTER: 
Yun-Yi Li
LAB HEAD: Yingqiu Li
PROVIDER: PXD078987 | Pride | 2026-07-07
REPOSITORIES: Pride
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| Lck-K273R_p62.msf | Msf | |||
| Lck-K273R_p62.raw | Raw | |||
| Lck-K273R_p62.xlsx | Xlsx | |||
| Lck-WT_p62.msf | Msf | |||
| Lck-WT_p62.raw | Raw |
Items per page: 5 1 - 5 of 7 |
Similar Datasets
Project description:DUSP22 (also named JKAP) is a dual-specificity phosphatase that inhibits T cell activation. Here we identified the E3 ubiquitin ligase UBR2 as an upstream activator of Lck during T-cell activation. JKAP dephosphorylated UBR2 at two residues, leading to ubiquitin-mediated UBR2 degradation. The SCF (SKP1-CUL1-βTrCP) complex induced UBR2 Lys48-linked ubiquitination at three lysine residues. Moreover, single-cell RNA sequencing analysis and UBR2 knockout showed that UBR2 increased proinflammatory cytokines. Remarkably, UBR2 induced Lys63-linked ubiquitination of Lck at two lysine residues and subsequent Lck Tyr394 phosphorylation/activation in TCR signaling. Conversely, TCR-induced Lck activation and JKAP knockout-enhanced inflammatory phenotypes were attenuated by UBR2 knockout. Consistently, the UBR2- Lck interaction and Lck Lys63-linked ubiquitination were induced in peripheral blood T cells of human SLE patients. Collectively, UBR2 protein stability and UBR2-induced Lck ubiquitination/activation are inhibited by JKAP, leading to attenuation of T-cell activation and T-cell-mediated inflammation.
2024-01-04 | PXD043457 | Pride
Project description:p62, a well-known adaptor of autophagy, plays multiple functions in response to various stresses. Here, we report a function for p62 in base excision repair that is distinct from its known functions. Loss of p62 impairs BER capacity and increases the sensitivity of cancer cells to alkylating and oxidizing agents. In response to alkylative and oxidative damage, p62 is accumulated in the nucleus，acetylated by hMOF， deacetylated by SIRT7, and acetylated p62 is recruited to chromatin. The chromatin-enriched p62 directly interacts with APE1, a key enzyme of the BER pathway, and promotes its endonuclease activity, which facilitates BER and cell survival. Collectively, our findings demonstrate that p62 is a regulator of BER, and provide further rationale for targeting p62 as a cancer therapeutic strategy.
2022-07-19 | PXD034901 | Pride
Project description:The tumor microenvironment plays a critical role in cancer progression, but the precise mechanisms by which stromal cells influence the tumor epithelium are poorly understood. The signaling adapter p62 has been implicated as a positive regulator of epithelial tumorigenesis; however, its role in the stroma is unknown. We show here that p62 levels are reduced in the stroma of several tumors. Also, orthotopic and organotypic studies demonstrate that the loss of p62 in the tumor microenvironment or stromal fibroblasts resulted in increased tumorigenesis of epithelial prostate cancer cells. The mechanism involves the regulation of cellular redox through an mTORC1/c-Myc pathway of stromal glucose and amino acid metabolism. Inhibition of the pathway by p62 deficiency results in increased stromal IL-6 production, which is required for tumor promotion in the epithelial compartment. Thus, p62 is an anti-inflammatory tumor suppressor that acts through modulation of metabolism in the tumor stroma. C57BL6 syngeneic TRAMP-C2Re3 cells (5×10^4) were injected orthotopically into the prostate of WT (n=6) or p62 KO (n=6) mice (C57BL6 background) and tumor growth was assessed, followed by transcriptome profiling of the orthotopic tumors (n=12).
2014-07-23 | E-GEOD-55587 | biostudies-arrayexpress
Project description:Lymphocyte-specific protein tyrosine kinase (Lck) is crucial for signaling from the T cell receptor (TCR) and is controlled through tyrosine phosphorylations. Phosphorylated Tyr505 (pTyr505) promotes a closed, inactive conformation of Lck, while pTyr394 is critical for kinase activity. Additionally, pTyr192 has been suggested to regulate Lck activity by changing the specificity of the Lck Src-homology 2 (SH2) domain and/or by affecting Lck association with CD45 thus drastically increasing pTyr505. However, little is known about how pTyr192 affects endogenously expressed Lck. Here we used CRISPR/Cas9 genome editing to generate Jurkat cell lines expressing Lck Glu192 mimicking Lck pTyr192, or Lck Phe192 mimicking unphosphorylated Lck Tyr192. We confirmed that Lck Glu192 is hyperphosphorylated on Tyr505, possibly explaining reduced association of Lck Glu192 with prototypic Lck-SH2 ligands. To isolate the effect of Lck Tyr192 mutations from the effect on Lck pTyr505, we subsequently generated Jurkat cells doubly mutated on Lck Tyr192 and Lck Tyr505. Both Lck Phe192/Phe505 and Lck Glu192/Phe505 mutants co-precipitated similar amounts of binding partners. Moreover, both mutants displayed hyperphosphorylation of Tyr394. Our results indicate that CD45 is the main phosphatase controlling Lck pTyr394 in steady-state T cells. Additionally, our data demonstrate that the prototypic specificity of the Lck SH2 domain (owned by the Lck Phe192 mutants) promotes transphosphorylation of Tyr394. These observations pinpoint the fundamental role of Tyr192 in regulation of Lck activity and simultaneously reveal the most potent Lck mutants so far described
2021-04-02 | PXD014470 | Pride
Project description:p62, a well-known adaptor of autophagy, plays multiple functions in response to various stresses. Here, we report a function for p62 in base excision repair that is distinct from its known functions. Loss of p62 impairs BER capacity and increases the sensitivity of cancer cells to alkylating and oxidizing agents. In response to alkylative and oxidative damage, p62 is accumulated in the nucleus，acetylated by hMOF， deacetylated by SIRT7, and acetylated p62 is recruited to chromatin. The chromatin-enriched p62 directly interacts with APE1, a key enzyme of the BER pathway, and promotes its endonuclease activity, which facilitates BER and cell survival. Collectively, our findings demonstrate that p62 is a regulator of BER, and provide further rationale for targeting p62 as a cancer therapeutic strategy.
2022-07-19 | PXD034899 | Pride
Project description:Inflammation is a driver of many diseases including cancer. Several studies have also shown that changes to macroautophagy can affect inflammation. We were interested in these connections and we report here that the autophagy adaptor proteins p62/SQSTM1 is cleaved upon treatment with the inflammatory cytokine TNF. Mass spectrometry and CRISPR analysis revealed this cleavage occurs at D329 and is mediated by caspase-8, to produce a short form of p63, which we term tr-p62. Our further analysis showed that cell death induced by TNF in the presence of Smac mimetics is not only dependent on p62, but intrinsically on its cleavage by caspase-8. Moreover, as inhibition of autophagy causes p62 accumulation and sensitizes cell to death, we show that this effect is also dependent on the production of tr-p62. Mechanistically, we show that tr-p62 is cleaved within and mediates a more stable caspase-8 activating complex, leading to a feed-forward loop of caspase-8 activation. Surprisingly, however, we found that mice belong to a very small group of mammals in which this caspase-8 cleavage site in p62 is absent. Introduction of either human p62 or a mutated cleavable version of mouse p62 into mouse cells renders them significantly more sensitive to cell death induced by TNF. Furthermore, we used CRISPR/Cas9 technology to make p62 cleavable on mice and we show that these mice are intrinsically sensitive to treatment with TNF. These findings therefore not only highlight a significant new step in the activation of cell death by TNF, but also provide a new mouse model that may provide better clarity for studies of mouse models of inflammatory disease.
2026-04-07 | PXD065587 | Pride
Project description:T cell antigen receptor (TCR) signaling depends upon the kinases Lck and Zap70. Lck phosphorylates the TCR, facilitating Zap70 recruitment to the stimulated TCR. Lck also phosphorylates Zap70, relieving its auto-inhibition and activating its catalytic domain. Zap70 then phosphorylates the critical adaptors LAT and SLP76 which serve to nucleate key effector molecules required for downstream responses. However, mechanisms facilitating the interaction of Zap70 with its substrates have not been described. We report an evolutionarily conserved proline-rich motif in LAT is important for Zap70-induced phosphorylation of LAT and downstream signaling. This LAT proline-rich motif associated with the Lck SH3 domain, thereby facilitating Zap70-mediated phosphorylation of LAT and downstream functions. Our results suggest Lck orchestrates multiple steps in TCR signaling including the newly described facilitation of the interaction of Zap70 with its substrate LAT. This previously unrecognized feature of TCR proximal signaling may contribute to the development of more immunomodulatory therapies.
2019-11-12 | PXD008258 | Pride
Project description:The Lck-OBF-1 construct used to generate transgenic mice contains an N-terminally HA epitope-tagged human OBF-1 cDNA under the control of the murine proximal lck promoter (-3100 to +23 relative to the transcription start site) that was purified by electroelution. Transgenic mouse lines were obtained and bred in B6CF1 x C57BL/6 background. For the analysis, age- and sex-matched littermates were used. The mice were kept in a standard mouse facility. Mice were sacrificed, the thymi were taken, rinsed in PBS and immediately homogenized in TRIZOL reagent (Life Technologies). Total RNA was prepared using TRIZOL reagent and purified on RNeasy Miniprep columns (Qiagen) according to the manufacturers' instructions. Array set (A1): Equal amounts of RNA from four young adult male mice (6.5 weeks old) per genotype were purified as stated above and pooled in equal amounts. Array set (A2): Equal amounts of total RNA from four young adult mice (6.5 weeks old; 2 males and 2 females each time) per genotype were purified as stated above and pooled in equal amounts. Both the WT and the transgenic pool were hybridized to Affymetrix GeneChips in duplicate. Array set (B): RNA was prepared from sorted thymic cell populations (CD4+ CD8+ CD25- and CD4+ CD8+ CD25+) from a pool of 15 young adult (mixed gender, 6 to 9 weeks of age) transgenic mice as stated above. Cell sorting was performed on a MoFlo (DakoCytomation) with a purity of at least 94%.
2006-10-25 | E-MEXP-85 | biostudies-arrayexpress
Project description:Mutations in proteins like FUS which cause Amyotrophic Lateral Sclerosis (ALS) result in the aberrant formation of stress granules while ALS-linked mutations in other proteins impede elimination of stress granules. Repeat expansions in C9ORF72, the major cause of ALS, reduce C9ORF72 levels but how this impacts stress granules is uncertain. Here, we demonstrate that C9ORF72 associates with the autophagy receptor p62 and controls elimination of stress granules by autophagy. This requires p62 to associate via the Tudor protein SMN with proteins, including FUS, that are symmetrically arginine-methylated by PRMT5. Mice lacking p62 accumulate arginine-methylated proteins and alterations in FUS-dependent splicing. Finally, patients with C9ORF72 repeat expansions accumulate symmetric arginine dimethylated proteins which co-localize with p62. This suggests that C9ORF72 initiates a cascade of ALS-linked proteins (C9ORF72, p62, SMN, FUS) to recognize stress granules for degradation by autophagy and hallmarks of a defect in this process are observable in ALS patients.
2018-07-26 | PXD009741 | Pride
Project description:DUSP22 (also named JKAP) is a dual-specificity phosphatase that inhibits T cell activation. Here we identified the E3 ubiquitin ligase UBR2 as an upstream activator of Lck during T-cell activation. JKAP dephosphorylated UBR2 at two residues, leading to ubiquitin-mediated UBR2 degradation. The SCF (SKP1-CUL1-βTrCP) complex induced UBR2 Lys48-linked ubiquitination at three lysine residues. Moreover, single-cell RNA sequencing analysis and UBR2 knockout showed that UBR2 increased proinflammatory cytokines. Remarkably, UBR2 induced Lys63-linked ubiquitination of Lck at two lysine residues and subsequent Lck Tyr394phosphorylation/activation in TCR signaling. Conversely, TCR-induced Lck activation and JKAP knockout-enhanced inflammatory phenotypes were attenuated by UBR2 knockout. Consistently, the UBR2-Lck interaction and Lck Lys63-linked ubiquitination were induced in peripheral blood T cells of human SLE patients. Collectively, UBR2 protein stability and UBR2-induced Lck ubiquitination/activation are inhibited by JKAP, leading to attenuation of T-cell activation and T-cell-mediated inflammation.
2024-01-04 | PXD043454 | Pride