当前位置： SCI文献检索 > GENETICS期刊下所有文献 > Coprinus cinereus rad50 mutants reveal an essential structural role for Rad50 in axial element and synaptonemal complex formation, homolog pairing and meiotic recombination.

Coprinus cinereus rad50 mutants reveal an essential structural role for Rad50 in axial element and synaptonemal complex formation, homolog pairing and meiotic recombination.

Abstract：

:The Mre11/Rad50/Nbs1 (MRN) complex is required for eukaryotic DNA double-strand break (DSB) repair and meiotic recombination. We cloned the Coprinus cinereus rad50 gene and showed that it corresponds to the complementation group previously named rad12, identified mutations in 15 rad50 alleles, and mapped two of the mutations onto molecular models of Rad50 structure. We found that C. cinereus rad50 and mre11 mutants arrest in meiosis and that this arrest is Spo11 dependent. In addition, some rad50 alleles form inducible, Spo11-dependent Rad51 foci and therefore must be forming meiotic DSBs. Thus, we think it likely that arrest in both mre11-1 and the collection of rad50 mutants is the result of unrepaired or improperly processed DSBs in the genome and that Rad50 and Mre11 are dispensable in C. cinereus for DSB formation, but required for appropriate DSB processing. We found that the ability of rad50 mutant strains to form Rad51 foci correlates with their ability to promote synaptonemal complex formation and with levels of stable meiotic pairing and that partial pairing, recombination initiation, and synapsis occur in the absence of wild-type Rad50 catalytic domains. Examination of single- and double-mutant strains showed that a spo11 mutation that prevents DSB formation enhances axial element (AE) formation for rad50-4, an allele predicted to encode a protein with intact hook region and hook-proximal coiled coils, but not for rad50-1, an allele predicted to encode a severely truncated protein, or for rad50-5, which encodes a protein whose hook-proximal coiled-coil region is disrupted. Therefore, Rad50 has an essential structural role in the formation of AEs, separate from the DSB-processing activity of the MRN complex.

journal_name

Genetics

journal_title

Genetics

authors

Acharya SN,Many AM,Schroeder AP,Kennedy FM,Savytskyy OP,Grubb JT,Vincent JA,Friedle EA,Celerin M,Maillet DS,Palmerini HJ,Greischar MA,Moncalian G,Williams RS,Tainer JA,Zolan ME

doi

10.1534/genetics.108.092775

subject

Has Abstract

pub_date

2008-12-01 00:00:00

pages

1889-907

issue

eissn

0016-6731

issn

1943-2631

pii

genetics.108.092775

journal_volume

180

pub_type

杂志文章

在线工具

Coprinus cinereus rad50 mutants reveal an essential structural role for Rad50 in axial element and synaptonemal complex formation, homolog pairing and meiotic recombination.