SUMOylation of the mitochondrial fission protein Drp1 occurs at multiple nonconsensus sites within the B domain and is linked to its activity cycle
SUMOylation of the mitochondrial fission protein Drp1 occurs at multiple nonconsensus sites within the B domain and is linked to its activity cycle
复制标题
DOI：
10.1096/fj.09-136630
复制
发表时间：
2009-11-01
期刊：
影响因子：
4.8
通讯作者：
Feldman, Eva L.
中科院分区：
文献类型：
--
作者：
Figueroa-Romero, Claudia;Iniguez-Lluhi, Jorge A.;Feldman, Eva L.
动力蛋白相关蛋白（Drp）1是线粒体分裂的关键调节因子，由GTP结合、中间、插入B和C末端GTP酶效应（GED）结构域组成。Drp 1与线粒体分裂位点相关，并通过其内在的GT3活性促进膜收缩。调节Drp 1活性的机制仍然知之甚少，但可能涉及可逆的翻译后修饰，如小泛素样修饰物（SUMO）蛋白的缀合。通过详细的分析，我们发现Drp 1与SUMO结合酶Ubc 9通过多个区域相互作用，并证明Drp 1是SUMO修饰的直接靶点。虽然Drp 1没有SUMO化序列，但我们的分析在B结构域中发现了2簇赖氨酸残基，它们是非典型的结合位点。虽然初步分析表明，异位表达的Drp 1响应星形孢菌素的线粒体招聘是不受SUMO化的损失，我们发现，Drp 1 SUMO化的K38 A突变的背景下增强。这种显性失活突变体缺乏GTP结合和水解，不与线粒体结合并阻止正常的线粒体分裂。这一发现表明Drp 1的SUMO化与其活性周期有关，并受到Drp 1定位的影响。Figueroa-Romero，C.，J. A.，Stadler，J.，昌角，澳-地R.，Arnoult，D.，凯勒，P. J.，洪，Y.，黑石，C.，Feldman，E. L.线粒体分裂蛋白Drp 1的SUMO化发生在B结构域内的多个非共有位点，并与其活性周期相关。FASEB J.23，3917-3927（2009）. www.fasebj.org
Dynamin-related protein (Drp) 1 is a key regulator of mitochondrial fission and is composed of GTP-binding, Middle, insert B, and C-terminal GTPase effector (GED) domains. Drp1 associates with mitochondrial fission sites and promotes membrane constriction through its intrinsic GTPase activity. The mechanisms that regulate Drp1 activity remain poorly understood but are likely to involve reversible post-translational modifications, such as conjugation of small ubiquitin-like modifier (SUMO) proteins. Through a detailed analysis, we find that Drp1 interacts with the SUMO-conjugating enzyme Ubc9 via multiple regions and demonstrate that Drp1 is a direct target of SUMO modification by all three SUMO isoforms. While Drp1 does not harbor consensus SUMOylation sequences, our analysis identified2 clusters of lysine residues within the B domain that serve as noncanonical conjugation sites. Although initial analysis indicates that mitochondrial recruitment of ectopically expressed Drp1 in response to staurosporine is unaffected by loss of SUMOylation, we find that Drp1 SUMOylation is enhanced in the context of the K38A mutation. This dominant-negative mutant, which is deficient in GTP binding and hydrolysis, does not associate with mitochondria and prevents normal mitochondrial fission. This finding suggests that SUMOylation of Drp1 is linked to its activity cycle and is influenced by Drp1 localization.-Figueroa-Romero, C., Iniguez-Lluhi, J. A., Stadler, J., Chang, C.-R., Arnoult, D., Keller, P. J., Hong, Y., Blackstone, C., Feldman, E. L. SUMOylation of the mitochondrial fission protein Drp1 occurs at multiple nonconsensus sites within the B domain and is linked to its activity cycle. FASEB J. 23, 3917-3927 (2009). www.fasebj.org