PTEN —— 磷酸酶和张力蛋白同系物

PTEN

磷酸酶和张力蛋白同系物

phosphatase and tensin homolog

该基因被鉴定为在许多癌症中高频率突变的抑癌基因。该基因编码的蛋白质是磷脂酰肌醇-3,4,5-三磷酸3-磷酸酶。它包含一个类似于双特异性蛋白酪氨酸磷酸酶的张力蛋白样结构域和一个催化结构域。与大多数蛋白质酪氨酸磷酸酶不同，该蛋白质优先使磷酸肌醇底物脱磷酸。它负调节细胞中磷脂酰肌醇-3,4,5-三磷酸的细胞内水平，并通过负调节AKT / PKB信号传导途径起抑癌作用。使用非规范（CUG）上游起始位点会产生更长的同工型，该异型可启动与亮氨酸的翻译，并被认为优先与线粒体内膜相关。这种更长的异构体可能有助于调节线粒体ು୔೎뗐愗愗೎繠痘V齠眊挀ો齠眊䡈ǀ䡈ǀ繠痘⌅痌轎ǍЀ￾￿￾￿ϰು繠痘
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This gene was identified as a tumor suppressor that is mutated in a large number of cancers at high frequency. The protein encoded by this gene is a phosphatidylinositol-3,4,5-trisphosphate 3-phosphatase. It contains a tensin like domain as well as a catalytic domain similar to that of the dual specificity protein tyrosine phosphatases. Unlike most of the protein tyrosine phosphatases, this protein preferentially dephosphorylates phosphoinositide substrates. It negatively regulates intracellular levels of phosphatidylinositol-3,4,5-trisphosphate in cells and functions as a tumor suppressor by negatively regulating AKT/PKB signaling pathway. The use of a non-canonical (CUG) upstream initiation site produces a longer isoform that initiates translation with a leucine, and is thought to be preferentially associated with the mitochondrial inner membrane. This longer isoform may help regulate energy metabolism in the mitochondria. A pseudogene of this gene is found on chromosome 9. Alternative splicing and the use of multiple translation start codons results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Feb 2015]