TY - JOUR
T1 - A genome-wide synthetic dosage lethality screen reveals multiple pathways that require the functioning of ubiquitin-binding proteins Rad23 and Dsk2
AU - Liu, Chang
AU - van Dyk, Dewald
AU - Li, Yue
AU - Andrews, Brenda
AU - Rao, Hai
N1 - Funding Information:
We thank the members of the Rao laboratory, especially Ikjin Kim, for stimulating discussions. The authors thank Drs. Charlie Boone and Michael Cos-tanzo for providing the SGA strain used to generate the double mutant for the SDL screen. HR is supported by the National Institutes of Health (GM078085). BA is supported by grants from the Canadian Institutes of Health Research (CIHR) and from Genome Canada through the Ontario Genomics Institute, and DvD is the recipient of a Fellowship from the Best Foundation.
PY - 2009/11/12
Y1 - 2009/11/12
N2 - Background: 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. Results: 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. Conclusion: 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.
AB - Background: 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. Results: 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. Conclusion: 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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U2 - 10.1186/1741-7007-7-75
DO - 10.1186/1741-7007-7-75
M3 - Article
C2 - 19909498
AN - SCOPUS:70749160910
SN - 1741-7007
VL - 7
SP - 75
JO - BMC Biology
JF - BMC Biology
M1 - 1741
ER -