PT  - JOURNAL ARTICLE
AU  - Bilge Argunhan
AU  - Masayoshi Sakakura
AU  - Negar Afshar
AU  - Misato Kurihara
AU  - Kentaro Ito
AU  - Takahisa Maki
AU  - Shuji Kanamaru
AU  - Yasuto Murayama
AU  - Hideo Tsubouchi
AU  - Masayuki Takahashi
AU  - Hideo Takahashi
AU  - Hiroshi Iwasaki
TI  - Rad51 Interaction Analysis Reveals a Functional Interplay Among Recombination Auxiliary Factors
AID  - 10.1101/738179
DP  - 2019 Jan 01
TA  - bioRxiv
PG  - 738179
4099  - http://biorxiv.org/content/early/2019/08/16/738179.short
4100  - http://biorxiv.org/content/early/2019/08/16/738179.full
AB  - Although Rad51 is the key protein in homologous recombination (HR), a major DNA double-strand break repair pathway, several auxiliary factors interact with Rad51 to promote productive HR. Here, we present an interdisciplinary characterization of the interaction between Rad51 and Swi5-Sfr1, a widely conserved auxiliary factor. NMR and site-specific crosslinking experiments revealed two distinct sites within the intrinsically disordered N-terminus of Sfr1 that cooperatively bind to Rad51. Although disruption of this binding severely impaired Rad51 stimulation in vitro, interaction mutants did not show any defects in DNA repair. Unexpectedly, in the absence of the Rad51 paralogs Rad55-Rad57, which constitute another auxiliary factor complex, these interaction mutants were unable to promote DNA repair. Our findings provide molecular insights into Rad51 stimulation by Swi5-Sfr1 and suggest that, rather than functioning in an independent subpathway of HR as was previously proposed, Rad55-Rad57 facilitates the recruitment of Swi5-Sfr1 to Rad51.