Alternative splicing of the metalloprotease ADAMTS17 spacer regulates secretion and modulates autoproteolytic activity.
Alternative splicing of the metalloprotease ADAMTS17 spacer regulates secretion and modulates autoproteolytic activity.
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金属蛋白酶ADAMTS17间隔区的选择性剪接调节分泌并调节自身蛋白水解活性。
DOI：
10.1096/fj.202001120rr
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发表时间：
2021-03
期刊：
影响因子：
--
通讯作者：
Hubmacher D
中科院分区：
文献类型：
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作者：
Balic Z;Misra S;Willard B;Reinhardt DP;Apte SS;Hubmacher D
ADAMTS蛋白酶在许多生理和疾病过程中介导分泌的细胞外基质（ECM）分子的生物合成和分解。除了它们的催化结构域之外，ADAMTS蛋白酶还含有辅助结构域，其介导底物识别和ECM结合，并赋予个体ADAMTS蛋白酶独特的性质和作用。虽然选择性剪接可以极大地扩展ADAMTS蛋白酶的结构和功能多样性，但很少有报道，并且很少对功能后果进行研究。在这里，我们描述ADAMTS 17的选择性剪接的结构和功能的影响，突变导致Weill-Marchesani综合征4。两个新的ADAMTS 17剪接变异体，ADAMTS 17 A和ADAMTS 17 B，通过结构建模，质谱和生化方法进行了研究。我们的研究结果确定了一种新的二硫键桥接插入ADAMTS 17 A间隔区，起源于包含一个新的外显子。这种插入导致ADAMTS 17的差异性自身蛋白水解，因此预测对其他底物的蛋白水解活性改变。第二种变体ADAMTS 17 B由框内外显子缺失引起，并阻止ADAMTS 17 B分泌。因此，ADAMTS间隔区的选择性剪接通过改变蛋白水解特异性（ADAMTS 17 A）或通过改变细胞定位（ADAMTS 17 B）来显著调节ADAMTS 17的生理学相关蛋白水解活性。
ADAMTS proteases mediate biosynthesis and breakdown of secreted extracellular matrix (ECM) molecules in numerous physiological and disease processes. In addition to their catalytic domains, ADAMTS proteases contain ancillary domains, which mediate substrate recognition and ECM binding and confer distinctive properties and roles to individual ADAMTS proteases. Although alternative splicing can greatly expand the structural and functional diversity of ADAMTS proteases, it has been infrequently reported and functional consequences have been rarely investigated. Here, we characterize the structural and functional impact of alternative splicing of ADAMTS17, mutations in which cause Weill-Marchesani syndrome 4. Two novel ADAMTS17 splice variants, ADAMTS17A and ADAMTS17B, were investigated by structural modeling, mass spectrometry, and biochemical approaches. Our results identify a novel disulfide-bridged insertion in the ADAMTS17A spacer that originates from inclusion of a novel exon. This insertion results in differential autoproteolysis of ADAMTS17, and thus, predicts altered proteolytic activity against other substrates. The second variant, ADAMTS17B, results from an in-frame exon deletion and prevents ADAMTS17B secretion. Thus, alternative splicing of the ADAMTS spacer significantly regulates the physiologically relevant proteolytic activity of ADAMTS17, either by altering proteolytic specificity (ADAMTS17A) or by altering cellular localization (ADAMTS17B).