Laboratory of Genome and Chromosome Functions

Member

Director Akira SHINOHARA
Assistant Professor Kenichiro MATSUZAKI
Kiran CHALLA

 

Correspondence

Tel 81-6-6879-8624
Fax 81-6-6879-8626
E-mail
URL http://www.protein.osaka-u.ac.jp/genome/english/

Research

Homologous recombination, an exchange between DNA strands, plays a role in the maintenance of genome stability and the production of genome diversity. While, in mitosis, it is required for the repair of DNA damage, it is for the segregation of homologous chromosome at meiotic division I. Meiotic recombination is coupled with chromosome morphogenesis and is under a strict control. Malfunction of the recombination leads cancer and infertility in human. In order to reveal molecular mechanism of the recombination, we have been analyzing genes and proteins involved in the process using molecular, genetical and biochemical methods.

 

09_1
Fig. 1: (A) A schematic pathway of assembly of protein machinery involved in homology search. RPA (green), Rad52 (red), Rad51 (blue).
(B) Rad51 filament on the DNA. It forms a right-handed helical filament.
(C) Rad51 forms a ring-like structure bound to DNAs.
09_2
Fig. 2: Synaptonemal complex (SC) formation. Immuno-staining analysis of the SC components, Zip1 (red) and Red1 (green) in the budding yeast. In SCs, paternal and maternal chromosomes are fully paired along chromosomes. Blue shows DNA, thus chromosomes.

 

Current Research Programs

  1. In vivo and in vivo analysis of recombination reactions
  2. Analysis of proteins working with RecA homologues in recombination
  3. Analysis of the roles of chromatin modification in meiotic recombination
  4. Mechanisms of choice of DSB repair pathways
  5. Analysis of recombination in human cells

References

  1. In vivo assembly and disassembly of Rad51 and Rad52 complexes during double-strand break repair. Miyazaki, T., Bressan, D. A., Shinohara, M., Haber, J. E., Shinohara, A. (2004) EMBO J. 23, 939-949.
  2. A protein complex containing Mei5 and Sae3 promotes the assembly of the meiosis-specific RecA homolog Dmc1. Hayase, A., Takagi, M., Miyazaki, T., Oshiumi, H., Shinohara, M., Shinohara, A. (2004) Cell 119, 927-940.
  3. Isolation and characterization of novel xrs2 mutations in Saccharomyce cerevisiae. Shima K., Suzuki M., Shinohara, M. (2005) Genetics 170, 71-85.