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Sequential posttranslational modifications regulate PKC degradation.

ABSTRACT: Cross-talk among different types of posttranslational modifications (PTMs) has emerged as an important regulatory mechanism for protein function. Here we elucidate a mechanism that controls PKC? stability via a sequential cascade of PTMs. We demonstrate that PKC? dephosphorylation decreases its sumoylation, which in turn promotes its ubiquitination and ultimately enhances its degradation via the ubiquitin-proteasome pathway. These findings provide a molecular explanation for the activation-induced down-regulation of PKC proteins.

SUBMITTER: Wang Y

PROVIDER: S-EPMC4713141 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Sequential posttranslational modifications regulate PKC degradation.

Wang Yan Y Wang Yangbo Y Zhang Huijun H Gao Yingwei Y Huang Chao C Zhou Aiwu A Zhou Yi Y Li Yong Y

Molecular biology of the cell 20151112 2

Cross-talk among different types of posttranslational modifications (PTMs) has emerged as an important regulatory mechanism for protein function. Here we elucidate a mechanism that controls PKCα stability via a sequential cascade of PTMs. We demonstrate that PKCα dephosphorylation decreases its sumoylation, which in turn promotes its ubiquitination and ultimately enhances its degradation via the ubiquitin-proteasome pathway. These findings provide a molecular explanation for the activation-induc ...[more]

PMID: 26564794

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