The de-ubiquitylating enzyme DUBA is essential for spermatogenesis in Drosophila
The de-ubiquitylating enzyme DUBA is essential for spermatogenesis in Drosophila
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DOI：
10.1038/cdd.2016.79
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发表时间：
2016-08
影响因子：
12.4
通讯作者：
L. Koerver;Juliane Melzer;E. Roca;Dominic Teichert;Timo Glatter;E. Arama;Meike Broemer
中科院分区：
文献类型：
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作者：
L. Koerver;Juliane Melzer;E. Roca;Dominic Teichert;Timo Glatter;E. Arama;Meike Broemer
去泛素化酶（DUBs）逆转蛋白质泛素化，从而控制基本的细胞功能。我们筛选了一种DUB，该DUB可以抵消caspase泛素化来调节细胞存活，我们鉴定了果蝇卵巢肿瘤型DUB DUBA （CG6091）。DUBA与caspase死亡调节因子Nedd2-like caspase （Dronc）发生物理相互作用并使其去泛素化，从而有效抑制凋亡拮抗剂诱导的蝇眼细胞凋亡。在寻找DUBA的非凋亡功能时，我们发现DUBA -null突变体是雄性不育的，并且在精子个体化中表现出缺陷，这一过程取决于非凋亡的半胱天冬酶活性。duba缺陷果蝇的精子显示半胱天冬酶活性降低，缺乏个性化过程的关键结构。生化表征揭示了DUBA通过磷酸化的专性激活步骤。通过基因修复实验，我们证明DUBA的磷酸化和催化活性对DUBA在精子发生中的功能至关重要。我们的研究结果首次证明了去泛素化对果蝇精子发生的重要性。
De-ubiquitylating enzymes (DUBs) reverse protein ubiquitylation and thereby control essential cellular functions. Screening for a DUB that counteracts caspase ubiquitylation to regulate cell survival, we identified the Drosophila ovarian tumour-type DUB DUBA (CG6091). DUBA physically interacts with the initiator caspase death regulator Nedd2-like caspase (Dronc) and de-ubiquitylates it, thereby contributing to efficient inhibitor of apoptosis-antagonist-induced apoptosis in the fly eye. Searching also for non-apoptotic functions of DUBA, we found that Duba-null mutants are male sterile and display defects in spermatid individualisation, a process that depends on non-apoptotic caspase activity. Spermatids of DUBA-deficient flies showed reduced caspase activity and lack critical structures of the individualisation process. Biochemical characterisation revealed an obligate activation step of DUBA by phosphorylation. With genetic rescue experiments we demonstrate that DUBA phosphorylation and catalytic activity are crucial in vivo for DUBA function in spermatogenesis. Our results demonstrate for the first time the importance of de-ubiquitylation for fly spermatogenesis.