|
|
"The Mus81/Mms4 endonuclease acts independently of double-Holliday junction resolution to promote a distinct subset of crossovers during meiosis in budding yeast."
|
de los Santos T, Hunter N, Lee C, Larkin B, Loidl J, Hollingsworth NM
|
Published May 1, 2003
in Genetics
volume 164
.
Pubmed ID:
12750322
Abstract:
Current models for meiotic recombination require that crossovers derive from the resolution of a double-Holliday junction (dHJ) intermediate. In prokaryotes, enzymes responsible for HJ resolution are well characterized but the identification of a eukaryotic nuclear HJ resolvase has been elusive. Indirect evidence suggests that MUS81 from humans and fission yeast encodes a HJ resolvase. We provide three lines of evidence that Mus81/Mms4 is not the major meiotic HJ resolvase in S. cerevisiae: (1) MUS81/MMS4 is required to form only a distinct subset of crossovers; (2) rather than accumulating, dHJ intermediates are reduced in an mms4 mutant; and (3) expression of a bacterial HJ resolvase has no suppressive effect on mus81 meiotic phenotypes. Our analysis also reveals the existence of two distinct classes of crossovers in budding yeast. Class I is dependent upon MSH4/MSH5 and exhibits crossover interference, while class II is dependent upon MUS81/MMS4 and exhibits no interference. mms4 specifically reduces crossing over on small chromosomes, which are known to undergo less interference. The correlation between recombination rate and degree of interference to chromosome size may therefore be achieved by modulating the balance between class I/class II crossovers.
|
This publication refers to following REPAIRtoire entries:
Last modification of this entry: Oct. 6, 2010
Add your own comment!
There is no comment yet.
|