Abstract
A cell cycle inhibitor group, KRPs (Kip-related proteins) from Arabidopsis consist of 7 molecular species. They may be divided into two groups based on their motif composition. Namely, AtKRP 3, 4, 5 have more than 7 motifs in each peptide. On the other hand, AtKRP1, 2, 6 and 7 have 4 or 5 motifs. Role of these motifs are not yet clear except 2-motifs that make CDK-cyclin binding domain at C-terminal. We have been interesting in roles of other motifs that might be contributed the binding to other functional protein(s).
To clarify the possibility, we have been tried to get binding protein(s) by yeast two-hybrid method. In this time, we mentioned to AtKRP3 with 7 motifs, because 1) which has many motifs, and 2) gene-expression pattern is quite unique. Namely, it is expressed in culture cells, but not in other tissues.
We screened 15 candidates from 30,000 yeast-colonies that have different cDNA from Arabidopsis young seedlings. These candidates include CDKA, unknown proteins and plastid-related proteins such as Rubisco small subunit. Now, we are checking on in vitro binding capacity between AtKRP3 and each candidate.
