title: The role of AtMSH2 in homologous recombination in Arabidopsis thaliana.
abstract: During homologous recombination (HR), a heteroduplex DNA is formed as a consequence of strand invasion. When the two homologous strands differ in sequence, a mismatch is generated. Earlier studies showed that mismatched heteroduplex often triggers abortion of recombination and that a pivotal component of this pathway is the mismatch repair Msh2 protein. In this study, we analysed the roles of AtMSH2 in suppression of recombination in Arabidopsis. We report that AtMSH2 has a broad range of anti-recombination effects: it suppresses recombination between divergent direct repeats in somatic cells or between homologues from different ecotypes during meiosis. This is the first example of a plant gene that affects HR as a function of sequence divergence and that has an anti-recombination meiotic effect. We discuss the implications of these results for plant improvement by gene transfer across species.
authors.affiliation: Department of Plant Sciences, Weizmann Institute of Science, Rehovot, Israel.
authors.forename: Eyal
authors.initials: E
authors.lastname: Emmanuel
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Yehuda
authors.forename: Cathy
authors.initials: C
authors.lastname: Melamed-Bessudo
authors.forename: Naomi
authors.initials: N
authors.lastname: Avivi-Ragolsky
authors.forename: Avraham A
authors.initials: AA
authors.lastname: Levy
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D020137:Base Pair Mismatch; D015415:Biomarkers / Q000378:metabolism; D004260:DNA Repair; D051718:MutS Homolog 2 Protein / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D011995:Recombination, Genetic
chemical_list: D029681:Arabidopsis Proteins; D015415:Biomarkers; D011993:Recombinant Fusion Proteins; C108984:MSH2 protein, Arabidopsis; D051718:MutS Homolog 2 Protein