TY - JOUR
T1 - Sts1 can overcome the loss of Rad23 and Rpn10 and represents a novel regulator of the ubiquitin/proteasome pathway
AU - Romero-Perez, Lizbeth
AU - Chen, Li
AU - Lambertson, David
AU - Madura, Kiran
PY - 2007/12/7
Y1 - 2007/12/7
N2 - A rad23Δ rpn10Δ double mutant accumulates multi-Ub proteins, is deficient in proteolysis, and displays sensitivity to drugs that generate damaged proteins. Overexpression of Sts1 restored normal growth in rad23Δ rpn10Δ but did not overcome the DNA repair defect of rad23Δ. To understand the nature of Sts1 suppression, we characterized sts1-2, a temperature-sensitive mutant. We determined that sts1-2 was sensitive to translation inhibitors, accumulated high levels of multi-Ub proteins, and caused stabilization of proteolytic substrates. Additionally, ubiquitinated proteins that were detected in proteasomes were inefficiently cleared in sts1-2. Despite these proteolytic defects, overall proteasome activity was increased in sts1-2. We propose that Sts1 is a new regulatory factor in the ubiquitin/proteasome pathway that controls the turnover of proteasome substrates.
AB - A rad23Δ rpn10Δ double mutant accumulates multi-Ub proteins, is deficient in proteolysis, and displays sensitivity to drugs that generate damaged proteins. Overexpression of Sts1 restored normal growth in rad23Δ rpn10Δ but did not overcome the DNA repair defect of rad23Δ. To understand the nature of Sts1 suppression, we characterized sts1-2, a temperature-sensitive mutant. We determined that sts1-2 was sensitive to translation inhibitors, accumulated high levels of multi-Ub proteins, and caused stabilization of proteolytic substrates. Additionally, ubiquitinated proteins that were detected in proteasomes were inefficiently cleared in sts1-2. Despite these proteolytic defects, overall proteasome activity was increased in sts1-2. We propose that Sts1 is a new regulatory factor in the ubiquitin/proteasome pathway that controls the turnover of proteasome substrates.
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U2 - 10.1074/jbc.M704857200
DO - 10.1074/jbc.M704857200
M3 - Article
C2 - 17916559
AN - SCOPUS:37249007155
SN - 0021-9258
VL - 282
SP - 35574
EP - 35582
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 49
ER -