p(HGNC:STUB1)
Several E3 Ub ligases, such as CHIP, Parkin, RNF182, may have roles in AD and other neurodegenerative diseases (Shimura et al., 2004; Khandelwal et al., 2011; Lei et al., 2012). PubMed:23528736
Alternatively, either Hsp70 or Hsp90 can recruit the ubiquitin E3 ligase, C-terminal Hsp70 interacting protein (CHIP), to degrade the bound substrate [104] PubMed:21882945
Alternatively, either Hsp70 or Hsp90 can recruit the ubiquitin E3 ligase, C-terminal Hsp70 interacting protein (CHIP), to degrade the bound substrate [104] PubMed:21882945
For example, BAG-2 inhibits client ubiquitination by CHIP by interfering with the interaction between CHIP and E2 ubiquitin-conjugating enzymes [148]. PubMed:21882945
CHIP has been linked to several neurodegenerative disorders including Huntington’s disease, Parkinson’s disease and AD as well as other diseases such as cystic fibrosis and cancer (Dickey et al., 2007b; Edkins, 2015). PubMed:29311797
CHIP has been linked to several neurodegenerative disorders including Huntington’s disease, Parkinson’s disease and AD as well as other diseases such as cystic fibrosis and cancer (Dickey et al., 2007b; Edkins, 2015). PubMed:29311797
CHIP has been linked to several neurodegenerative disorders including Huntington’s disease, Parkinson’s disease and AD as well as other diseases such as cystic fibrosis and cancer (Dickey et al., 2007b; Edkins, 2015). PubMed:29311797
CHIP has been linked to several neurodegenerative disorders including Huntington’s disease, Parkinson’s disease and AD as well as other diseases such as cystic fibrosis and cancer (Dickey et al., 2007b; Edkins, 2015). PubMed:29311797
CHIP has been linked to several neurodegenerative disorders including Huntington’s disease, Parkinson’s disease and AD as well as other diseases such as cystic fibrosis and cancer (Dickey et al., 2007b; Edkins, 2015). PubMed:29311797
In particular, previous studies have demonstrated that the tau ubiquitin ligase, CHIP, is unable to bind and ubiquitinate tau species phosphorylated by Par-1/MARK2 on the 12E8 epitope (S262/356) [33], a p-tau species that is also resistant to degradation upon treatment with Hsp90 inhibitors [32,33]. Tau phosphorylated at the PHF1 epitope (S396/404) is still susceptible to degradation following Hsp90 inhibition and actually exhibits an enhanced interaction with Hsp90 PubMed:25031639
the ACR (APP cytosolic region) interacts with the E3 ubiquitin-protein ligases Stub1, which binds the NH2 terminus of the ACR, and CRL4(CRBN), which is formed by Cul4a/b, Ddb1, and Crbn, and interacts with the COOH terminus of the ACR via Crbn. PubMed:27325702
Recent data suggest that caspases are involved in the accumulation of tau pathology [10, 25, 26], and reductions in CHIP have been shown to cause caspase activation and increased caspase-cleaved tau levels [19]. PubMed:25374103
Recent data suggest that caspases are involved in the accumulation of tau pathology [10, 25, 26], and reductions in CHIP have been shown to cause caspase activation and increased caspase-cleaved tau levels [19]. PubMed:25374103
Two subnetworks emerged within this central network, corresponding to known Hsp90 and Hsp70 chaperone complexes (Figure 2, blue and orange squares, respectively). These two subnetworks were bridged by a unique set of cochaperones (Figure 2, tan squares). Among these were the wellknown bridging factors HOP/STIP1, TPR2/DNAJC7, and CHIP/ STUB1, validating our approach (Brychzy et al., 2003; Schmid et al., 2012; Xu et al., 2002). Other bridging factors in this first tier of organization included members of the Hsp40 chaperone family (DNAJB1 and DNAJB6), HSP70-binding protein 1 (HSPBP1), the TPR domain protein EDRF1, and the E3 ligase NRDP1/RNF41 PubMed:25036637
CHIP binds Hsp90 and Hsp70 with similar affinities and can regulate the degradation of chaperone clients (Kundrat and Regan, 2010). PubMed:25036637
CHIP binds Hsp90 and Hsp70 with similar affinities and can regulate the degradation of chaperone clients (Kundrat and Regan, 2010). PubMed:25036637
CHIP binds Hsp90 and Hsp70 with similar affinities and can regulate the degradation of chaperone clients (Kundrat and Regan, 2010). PubMed:25036637
However, another study, also using HEK cells and ubiquitin K48 and K63 mutants, demonstrated that in the presence of the E3 ligase CHIP, tau could be ubiquitylated by both K48 and K63 linkages (100). The likelihood that in vivo tau can be ubiquitylated in multiple ways is supported by studies showing tau isolated from NFTs in human brain has several forms of ubiquitin linkages as well as mono-ubiquitylation (101, 102). These data suggest that the physical structure of the ubiquitin chain is unlikely to be a sufficient signal for selectively targeting tau to either the proteasome or autophagy. PubMed:24027553
Several E3 Ub ligases, such as CHIP, Parkin, RNF182, may have roles in AD and other neurodegenerative diseases (Shimura et al., 2004; Khandelwal et al., 2011; Lei et al., 2012). PubMed:23528736
Alternatively, either Hsp70 or Hsp90 can recruit the ubiquitin E3 ligase, C-terminal Hsp70 interacting protein (CHIP), to degrade the bound substrate [104] PubMed:21882945
For example, BAG-2 inhibits client ubiquitination by CHIP by interfering with the interaction between CHIP and E2 ubiquitin-conjugating enzymes [148]. PubMed:21882945
CHIP has been linked to several neurodegenerative disorders including Huntington’s disease, Parkinson’s disease and AD as well as other diseases such as cystic fibrosis and cancer (Dickey et al., 2007b; Edkins, 2015). PubMed:29311797
CHIP has been linked to several neurodegenerative disorders including Huntington’s disease, Parkinson’s disease and AD as well as other diseases such as cystic fibrosis and cancer (Dickey et al., 2007b; Edkins, 2015). PubMed:29311797
CHIP has been linked to several neurodegenerative disorders including Huntington’s disease, Parkinson’s disease and AD as well as other diseases such as cystic fibrosis and cancer (Dickey et al., 2007b; Edkins, 2015). PubMed:29311797
CHIP has been linked to several neurodegenerative disorders including Huntington’s disease, Parkinson’s disease and AD as well as other diseases such as cystic fibrosis and cancer (Dickey et al., 2007b; Edkins, 2015). PubMed:29311797
CHIP has been linked to several neurodegenerative disorders including Huntington’s disease, Parkinson’s disease and AD as well as other diseases such as cystic fibrosis and cancer (Dickey et al., 2007b; Edkins, 2015). PubMed:29311797
In tauopathic mice, CHIP regulates the removal of tau species that have undergone abnormal phosphorylation and folding (Dickey et al., 2007b). PubMed:29311797
In tauopathic mice, CHIP regulates the removal of tau species that have undergone abnormal phosphorylation and folding (Dickey et al., 2007b). PubMed:29311797
In particular, previous studies have demonstrated that the tau ubiquitin ligase, CHIP, is unable to bind and ubiquitinate tau species phosphorylated by Par-1/MARK2 on the 12E8 epitope (S262/356) [33], a p-tau species that is also resistant to degradation upon treatment with Hsp90 inhibitors [32,33]. Tau phosphorylated at the PHF1 epitope (S396/404) is still susceptible to degradation following Hsp90 inhibition and actually exhibits an enhanced interaction with Hsp90 PubMed:25031639
In particular, previous studies have demonstrated that the tau ubiquitin ligase, CHIP, is unable to bind and ubiquitinate tau species phosphorylated by Par-1/MARK2 on the 12E8 epitope (S262/356) [33], a p-tau species that is also resistant to degradation upon treatment with Hsp90 inhibitors [32,33]. Tau phosphorylated at the PHF1 epitope (S396/404) is still susceptible to degradation following Hsp90 inhibition and actually exhibits an enhanced interaction with Hsp90 PubMed:25031639
the ACR (APP cytosolic region) interacts with the E3 ubiquitin-protein ligases Stub1, which binds the NH2 terminus of the ACR, and CRL4(CRBN), which is formed by Cul4a/b, Ddb1, and Crbn, and interacts with the COOH terminus of the ACR via Crbn. PubMed:27325702
For example, overexpression of the human TPR domain-containing co- chaperone CHIP suppresses neurodegeneration in fly models expressing polyQ-containing versions of ataxin 1 and the N-terminal huntingtin fragment (Al-Ramahi et al., 2006). PubMed:27491084
On the other hand, it has been reported that the E3 ligase CHIP (carboxyl terminus of the Hsc70-interacting protein) binds to tau and is involved in the degradation of abnormal forms of tau, including insoluble tau and hyperphosphorylated tau, coordinately with Hsp70 (Petrucelli et al. 2004; Dickey et al. 2006). PubMed:22908190
CHIP is also implicated in regulation of Caspase 3 activity PubMed:25374103
CHIP interacts more strongly with tauΔC than full-length tau [18], suggesting it is involved in caspase cleaved tau degradation PubMed:25374103
Recent data suggest that a critical mediator of refolding or clearance of hyperphosphorylated tau is via the HSP70/HSP90 heat shock pathways in which a specific E3 ubiquitin ligase, CHIP (carboxy terminus Hsp70 interacting protein), can recognize and target for degradation abnormal but not normal tau molecules [14–16]. PubMed:25374103
Dolan et al. [20] showed that CHIP interacts more strongly with tauC3 than full length tau. PubMed:25374103
CHIP interacts more strongly with tauΔC than full-length tau [18], suggesting it is involved in caspase cleaved tau degradation PubMed:25374103
Recent data suggest that caspases are involved in the accumulation of tau pathology [10, 25, 26], and reductions in CHIP have been shown to cause caspase activation and increased caspase-cleaved tau levels [19]. PubMed:25374103
These results indicate that CHIP is involved in degradation of caspases and caspase-cleaved tau. PubMed:25374103
Toxicity assays revealed that neither CHIP nor any of the tau constructs caused cell death compared to the control GFP vector (Supplementary Fig. 1). PubMed:25374103
The co-chaperone CHIP interacts with Hsp70/Hsp90 to bind unfolded and misfolded proteins PubMed:25374103
The co-chaperone CHIP interacts with Hsp70/Hsp90 to bind unfolded and misfolded proteins PubMed:25374103
Either of these domains could be critical for degradation of tau since ubiquitination targets proteins for degradation and CHIP is known to interact with full-length tau in a complex with Hsc70/Hsp70 and poly-ubiquitinated tau [17]. PubMed:25374103
After cyclohexamide treatment, we could still detect a significant decrease in tau levels in cells that were co-transfected with CHIP indicating that the reduction in tau levels due to CHIP is due to degradation and not to transcriptional down-regulation (Supplementary Fig. 3). PubMed:25374103
Recent data suggest that caspases are involved in the accumulation of tau pathology [10, 25, 26], and reductions in CHIP have been shown to cause caspase activation and increased caspase-cleaved tau levels [19]. PubMed:25374103
These results indicate that CHIP is involved in degradation of caspases and caspase-cleaved tau. PubMed:25374103
Dolan et al. [20] showed that CHIP interacts more strongly with tauC3 than full length tau. PubMed:25374103
Tau is known to be ubiquitylated through Lys48 linkages by CHIP for proteasomal degradation PubMed:26631930
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If you find BEL Commons useful in your work, please consider citing: Hoyt, C. T., Domingo-Fernández, D., & Hofmann-Apitius, M. (2018). BEL Commons: an environment for exploration and analysis of networks encoded in Biological Expression Language. Database, 2018(3), 1–11.