Candida albicans Cdc37 interacts with the Crk1 kinase and is required for Crk1 production.
Crk1, a Cdc2-related protein kinase from the human pathogenic fungus Candida albicans, plays an important role in hyphal development and virulence. To address its regulatory mechanisms, we searched for Crk1 interacting proteins by two-hybrid screening. A CDC37 ortholog (CaCDC37) was cloned from the screening with the Crk1 kinase domain as the bait. The CaCdc37 interacted preferentially with the kinase domain of Crk1 (Crk1N) as shown by two-hybrid and immunoprecipitation experiments. CaCDC37 could complement a cdc37 thermosensitive mutant (cdc37-34) of Saccharomyces cerevisiae. Importantly, Crk1 protein was hardly detectable in the cdc37-34 mutant at restrictive temperature. However, upon expression of CaCdc37 in the cdc37 mutant, Crk1 protein was detected even at restrictive temperature. Our data suggested that CaCdc37 was required for the production of Crk1 kinase. Like Cdc37 proteins of S. cerevisiae and higher eukaryotes, CaCdc37 might function as a molecular chaperone that stabilized Crk1 and other protein kinases in C. albicans. In support of this, CaSTI1 was identified from a two-hybrid screen with the full-length Crk1 as the bait. CaSti1 showed two-hybrid interactions with both Crk1 and the CaCdc37.
Ni
Jian
J
State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue-yang Road, Shanghai 200031, PR China.
Gao
Yankun
Y
Liu
Haopin
H
Chen
Jiangye
J
D000595:Amino Acid Sequence; D002176:Candida albicans / Q000737:chemistry*; D018797:Cell Cycle Proteins / Q000378:metabolism* / Q000502:physiology; D018833:Chaperonins; D029721:Drosophila Proteins / Q000378:metabolism* / Q000502:physiology; D005656:Fungal Proteins / Q000378:metabolism; D006360:Heat-Shock Proteins; D018832:Molecular Chaperones / Q000378:metabolism* / Q000502:physiology; D008969:Molecular Sequence Data; D011233:Precipitin Tests; D011485:Protein Binding; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis* / Q000378:metabolism*; D050737:Proto-Oncogene Proteins c-crk; D029701:Saccharomyces cerevisiae Proteins; D016415:Sequence Alignment; D013696:Temperature; D020798:Two-Hybrid System Techniques
C513270:CDC37 protein, S cerevisiae; C498362:CDC37 protein, human; D018797:Cell Cycle Proteins; D029721:Drosophila Proteins; D005656:Fungal Proteins; D006360:Heat-Shock Proteins; D018832:Molecular Chaperones; D011518:Proto-Oncogene Proteins; D050737:Proto-Oncogene Proteins c-crk; C542289:STI1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D018833:Chaperonins