title: The Saccharomyces cerevisiae ubiquitin E3 ligase Asr1p targets calmodulin for ubiquitylation.
abstract: Yeast calmodulin known to be ubiquitylated in vivo in a Ca(2+) dependent manner has long remained an orphan substrate. Here we identify Saccharomyces cerevisiae Asr1p as an ubiquitin E3 ligase for yeast calmodulin, a protein involved in calcium signaling. A short region within Asr1p-C harboring two putative calmodulin-binding motifs is sufficient and necessary for interaction with calmodulin. The interaction is direct, occurs in vivo and depends on physiological concentrations of Ca(2+). A minimal set of purified proteins including Asr1p E3 ligase was sufficient for in vitro ubiquitylation of calmodulin, a reaction that required a functional Asr1p Ring domain. We propose a role of the Asr1p E3 ligase activity in coping with stress.
authors: Max-von-Pettenkofer-Institut, Pettenkoferstr. 9a, Ludwig-Maximilian-Universität München, 80336 München, Germany.
authors: Thomas
authors: T
authors: Fries
authors: Ronald
authors: R
authors: Frank
authors: Susanne M
authors: SM
authors: Bailer
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D002118:Calcium / Q000378:metabolism*; D002147:Calmodulin / Q000378:metabolism*; D008969:Molecular Sequence Data; D012441:Saccharomyces cerevisiae / Q000201:enzymology*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D013312:Stress, Physiological; D054875:Ubiquitination
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C488254:Asr1 protein, S cerevisiae; C505601:CMD1 protein, S cerevisiae; D002147:Calmodulin; D029701:Saccharomyces cerevisiae Proteins; D002118:Calcium