Analysis of
Phosphorylation of YJL084c, a Yeast Protein
SHI Xiao-Zhong, AO Shi-Zhou*
( State Key Laboratory of Molecular Biology, Institute of Biochemistry and
Cell biology, Shanghai Institutes for Biological Sciences, the Chinese Academy
of Sciences, Shanghai 200031, China )
Abstract PCL6,
PCL7(PAP1), and PHO80 belong to the PHO80 subfamily of PCLs (PHO85 cyclins), share
high homology in protein sequences, and function with some similarity. YLR190w,
the substrate of PCL7-PHO85, shares homology with YJL084c in a 140-amino-acid
region. In addition, YJL084c was reported as a PCL6-binding protein. Here, it
was found that there was association between YJL084c and PCL7, and their
interaction was confirmed by co-immunoprecipitation assay and GST pull-down
assay. The in vitro translational product of YJL084c could be
phosphorylated by PCL7-PHO85 complex. Also, the GST fusion protein of the
middle region expressed in E.coli could be phosphorylated, while the
amino terminal or the carboxyl terminal could not. Interestingly, PCL6-PHO85
complex had the same characters; effect of phosphate condition on the
phosphorylation was shown in both PCL6-PHO85 and PCL7-PHO85. YPH499: Yjl084c
¡Ë LEU2 was constructed by homologous recombination. PUT4 was reported as
a YJL084c-binding protein, but no difference was observed between wild strain
and the Yjl084c null mutant on MP medium. In addition, the
interaction between PHO81 and all of the three cyclins was analyzed.
Key words PCL6£» PCL7£» YJL084c£» phosphorylation£» yeast two-hybrid system
*Corresponding author: Tel,
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