High impact information on BUL1

• A second mutation, smm2, which also suppressed mdm1-252 defects, but did not cause aberrant mitochondrial distribution and morphology, mapped to BUL1, encoding a protein interacting with Rsp5p [1].
• Suppression of temperature sensitivity by an osmotic stabilizer is also observed in the bul1 bul2 double null mutant, and the temperature sensitivity of the bul1 bul2 double null mutant is suppressed by multiple copies of MCK1 [2].
• We find that Rog1, but not Rog2, is stabilized in the gsk-3 null and the bul1 bul2 double null mutants [2].
• Thus, we named our gene BUL1 (for a protein that binds to the ubiquitin ligase) [3].
• Coexpression of RSP5 and BUL1 on a multicopy plasmid was toxic for mitotic growth of the wild-type cells [3].

Biological context of BUL1

• We demonstrate here that heat shock element (HSE)-mediated gene expression was defective in both rsp5-101 and bul1 bul2 mutants under high temperature condition [4].
• A chromosomal BUL1 deletion displayed all phenotypes shown by the PB-resistant mutant [5].

Associations of BUL1 with chemical compounds

• Furthermore, both Bul1 and Rsp5 appeared to be associated with large complexes which were separated through a sucrose gradient centrifugation, and Rsp5 was coimmunoprecipitated with Bul1 [3].

Physical interactions of BUL1

• The previously identified BUL1 gene was found to encode a protein bound to Rsp5-ubiquitin ligase in budding yeast [6].

Regulatory relationships of BUL1

• Thus, NPR1 and BUL1/2 antagonistically control GLN3-dependent transcription, suggesting a role for regulated ubiquitination in the control of nutrient-responsive transcription [7].

Other interactions of BUL1

• We have identified the BUL2 gene as a functional homologue of BUL1 [6].
• Rsp5-Bul1/2 complex is necessary for the HSE-mediated gene expression in budding yeast [4].
• Thus, the Rsp5-Bul1/2 complex has a new function for the HSE-mediated gene expression and may regulate it through other factors than Hsf1 [4].

Analytical, diagnostic and therapeutic context of BUL1

• Since the steady-state levels of the protein were the same in the two strains as determined by immunoblotting analysis, Bul1 might be easily degraded during immunoprecipitation in the absence of intact Rsp5 [3].

References