AtMSH5 partners AtMSH4 in the class I meiotic crossover pathway in Arabidopsis thaliana, but is not required for synapsis.

James Higgins, J Vignard, R Mercier, AG Pugh, Frederick Franklin, Gareth Jones

Research output: Contribution to journalArticle

89 Citations (Scopus)


MSH5, a meiosis-specific member of the MutS-homologue family of genes, is required for normal levels of recombination in budding yeast, mouse and Caenorhabditis elegans. In this paper we report the identification and characterization of the Arabidopsis homologue of MSH5 (AtMSH5). Transcripts of AtMSH5 are specific to reproductive tissues, and immunofluorescence studies indicate that expression of the protein is abundant during prophase I of meiosis. In a T-DNA tagged insertional mutant (Atmsh5-1), recombination is reduced to about 13% of wild-type levels. The residual chiasmata are randomly distributed between cells and chromosomes. These data provide further evidence for at least two pathways of meiotic recombination in Arabidopsis and indicate that AtMSH5 protein is required for the formation of class I interference-sensitive crossovers. Localization of AtMSH5 to meiotic chromosomes occurs at leptotene and is dependent on DNA double-strand break formation and strand exchange. Localization of AtMSH5 to the chromatin at mid-prophase I is dependent on expression of AtMSH4. At late zygotene/early pachytene a proportion of AtMSH5 foci co-localize with AtMLH1 which marks crossover-designated sites. Chromosome synapsis appears to proceed normally, without significant delay, in Atmsh5-1 but the pachytene stage is extended by several hours, indicative of the operation of a surveillance system that monitors the progression of prophase I.
Original languageEnglish
Pages (from-to)28-39
Number of pages12
JournalThe Plant journal : for cell and molecular biology
Issue number1
Publication statusPublished - 1 Jul 2008


  • meiosis
  • crossover
  • MSH5
  • Arabidopsis
  • chromosome synapsis


Dive into the research topics of 'AtMSH5 partners AtMSH4 in the class I meiotic crossover pathway in Arabidopsis thaliana, but is not required for synapsis.'. Together they form a unique fingerprint.

Cite this