A genome-wide synthetic dosage lethality screen reveals multiple pathways that require the functioning of ubiquitin-binding proteins Rad23 and Dsk2.
A genome-wide synthetic dosage lethality screen reveals multiple pathways that require the functioning of ubiquitin-binding proteins Rad23 and Dsk2.
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DOI：
10.1186/1741-7007-7-75
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发表时间：
2009-11-12
期刊：
影响因子：
5.4
通讯作者：
Rao H
中科院分区：
文献类型：
--
作者：
Liu C;van Dyk D;Li Y;Andrews B;Rao H
泛素通过与底物的共价结合来调节细胞内的许多重要过程。泛素的一个经典作用是标记蛋白质以被蛋白酶体破坏。最近的研究表明，泛素结合蛋白（如Rad23，Dsk 2，Rpn 10）在将泛素化蛋白转移到蛋白酶体中起着关键作用。然而，这些泛素受体的具体作用仍然不清楚。解开这些泛素受体功能的关键是确定它们的细胞底物和它们参与的生物回路。虽然已经开发了许多策略用于底物分离，但蛋白水解途径的生理靶标的鉴定已被证明是相当具有挑战性的。使用全基因组功能筛选，我们已经确定了11个酵母基因，它们在缺乏两个泛素结合蛋白Rad23和Dsk 2的细胞中过表达时会导致生长缓慢。我们的研究结果表明，Rad23和Dsk2的正常功能是有效的信息素反应，转录，氨基酸代谢和DNA损伤反应所必需的。通过筛选鉴定的两种蛋白质显示为Dsk 2的蛋白水解底物，验证了大规模合成剂量致死筛选作为鉴定特定降解途径底物的新策略。总之，作为概念验证，我们表明，合成剂量致死筛选，这是基于基因过表达诱导的毒性，提供了一种有效的，互补的方法来阐明蛋白水解途径的生物学功能。
Ubiquitin regulates a myriad of important cellular processes through covalent attachment to its substrates. A classic role for ubiquitin is to flag proteins for destruction by the proteasome. Recent studies indicate that ubiquitin-binding proteins (e.g. Rad23, Dsk2, Rpn10) play a pivotal role in transferring ubiquitylated proteins to the proteasome. However, the specific role of these ubiquitin receptors remains poorly defined. A key to unraveling the functions of these ubiquitin receptors is to identify their cellular substrates and biological circuits they are involved in. Although many strategies have been developed for substrate isolation, the identification of physiological targets of proteolytic pathways has proven to be quite challenging. Using a genome-wide functional screen, we have identified 11 yeast genes that cause slower growth upon their overexpression in cells lacking two ubiquitin-binding proteins Rad23 and Dsk2. Our results suggest that proper functioning of Rad23 and Dsk2 is required for efficient pheromone response, transcription, amino acid metabolism, and DNA damage response. Two proteins identified by the screen are shown to be proteolytic substrates of Dsk2, validating the large scale synthetic dosage lethality screen as a new strategy for identifying substrates of a specific degradation pathway. In conclusion, as proof-of-concept, we show that a synthetic dosage lethality screen, which is based on the toxicity induced by gene overexpression, offers an effective, complementary method to elucidating biological functions of proteolytic pathways.
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影响因子：
2.7
作者：
Liu, Chang;Apodaca, Jennifer;Rao, Hai
通讯作者：
Rao, Hai
影响因子：
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通讯作者：
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