General Comment |
Deubiquitinase YOD1 potentiates YAP/TAZ activities through enhancing ITCH stability. Kim Y et al. (2017) Hippo signaling controls the expression of genes regulating cell proliferation and survival and organ size. The regulation of core components in the Hippo pathway by phosphorylation has been extensively investigated, but the roles of ubiquitination-deubiquitination processes are largely unknown. To identify deubiquitinase(s) that regulates Hippo signaling, we performed unbiased siRNA screening and found that YOD1 controls biological responses mediated by YAP/TAZ. Mechanistically, YOD1 deubiquitinates ITCH, an E3 ligase of LATS, and enhances the stability of ITCH, which leads to reduced levels of LATS and a subsequent increase in the YAP/TAZ level. Furthermore, we show that the miR-21-mediated regulation of YOD1 is responsible for the cell-density-dependent changes in YAP/TAZ levels. Using a transgenic mouse model, we demonstrate that the inducible expression of YOD1 enhances the proliferation of hepatocytes and leads to hepatomegaly in a YAP/TAZ-activity-dependent manner. Moreover, we find a strong correlation between YOD1 and YAP expression in liver cancer patients. Overall, our data strongly suggest that YOD1 is a regulator of the Hippo pathway and would be a therapeutic target to treat liver cancer.//////////////////
NCBI Summary:
This gene encodes a member of the Nedd4 family of HECT domain E3 ubiquitin ligases. HECT domain E3 ubiquitin ligases transfer ubiquitin from E2 ubiquitin-conjugating enzymes to protein substrates, thus targeting specific proteins for lysosomal degradation. The encoded protein plays a role in multiple cellular processes including erythroid and lymphoid cell differentiation and the regulation of immune responses. Mutations in this gene are a cause of syndromic multisystem autoimmune disease. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Mar 2012]
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Mutations |
1 mutations
Species: mouse
Mutation name:
type: null mutation
fertility: subfertile
Comment: Female mice with loss-of-function ITCH display an altered reproductive phenotype. Stermer AR et al. (2015) Major progress in deciphering the role of the E3 ligase, ITCH, in animal physiology has come from the generation and identification of Itch loss-of-function mutant mice (itchy). Mutant mice display an autoimmune-like phenotype characterized by chronic dermatitis, which has been attributed to increased levels of ITCH target proteins (e.g. transcription factors JUNB and CJUN) in T cells. Autoimmune disorders also exist in humans with Itch frameshift mutations resulting in loss of functional ITCH protein. Recent phenotypic analysis of male itchy mice revealed reduced sperm production, although cross breeding experiments showed no difference in litter size when male itchy mice were bred to wild type females. However, a reduction in litter sizes did occur when itchy females were bred to wild type males. Based on these results, characterization of female reproductive function in itchy mice was performed. Developmental analysis of fetuses at gestational day 18.5, cytological evaluation of estrous cyclicity, histopathological analysis of ovaries, and protein analysis were used to investigate the itchy reproductive phenotype. Gross skeletal and soft tissue analysis of gestational day 18.5 itchy fetuses indicated no gross developmental deformities. Itchy females had reduced implantation sites, decreased corpora lutea, and increased estrous cycle length due to increased number of days in estrus compared to controls. Alterations in the expression of prototypical ITCH targets in the ovaries were not indicated, suggesting that an alteration in an as yet defined ovary-specific ITCH substrate or interaction with the altered immune system likely accounts for the disruption of female reproduction. This report indicates the importance of the E3 ligase, ITCH, in female reproduction.//////////////////
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