FBXW7是抑癌基因，编码蛋白是一种参与蛋白质降解的F-box蛋白亚基。编码蛋白通过SCF（Skp1-Cul1-F-box蛋白）型泛素连接酶复合物参与底物识别，识别底物后该复合物修饰底物，使其靶向蛋白质降解。FBXW7的底物包括蛋白c-MYC，mTOR，NOTCH1，细胞周期蛋白-E和JUN。FBXW7通过突变或拷贝数丢失导致自身蛋白失活，进而导致癌蛋白的异常积累，随后促成恶性转化。FBXW7的有三种常见剪接，形成三种不同的蛋白质同种型（α，β，γ），每种具有差异定位。FBXW7中的突变可以负面影响同种型特异性功能，亚基的二聚化，蛋白质定位，SCF装配或底物识别。FBXW7中的大多数突变是破坏底物结合的点突变，而<10％是小缺失或插入。FBXW7失活突变最常见于子宫内膜癌和结直肠癌。

FBXW7 gene encodes an F-box protein subunit involved in substrate recognition by an SCF (Skp1-Cul1-F-box protein)-type ubiquitin ligase complex. Upon substrate identification, this complex modifies the substrate such that it is targeted for protein degradation. Substrates of FBXW7 include the proteins c-MYC, mTOR, NOTCH1, cyclin-E, and JUN, which are instrumental in the regulation of cell division, differentiation and growth, and which are often inappropriately activated in cancer. As most FBXW7 substrates are proto-oncogenes that are processed for degradation by the SCF complex, FBXW7 functions as a tumor suppressor. Inactivation of FBXW7 by mutation or copy number loss results in aberrant accumulation of oncoproteins, which subsequently contributes to malignant transformation. Alternate splicing of FBXW7 results in three distinct protein isoforms (α, β, γ) each with differential localization. Mutations in FBXW7 can negatively affect isoform-specific functions, dimerization of subunits, protein localization, SCF assembly or substrate recognition. Most mutations in FBXW7 are point mutations that disrupt substrate binding, while <10% are small deletions or insertions.

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