Mismatch Repair Systems in Arabidopsis

Oregon State University, Corvallis OR

Investigators

Abstract

Abstract In eukaryotes, MSLH systems composed of homologs of prokaryotic MutS proteins and of MutL proteins mediate critical genomic stability functions. Plants encode several MSH proteins whose activities would appear needed to prevent accumulation of replication-error and environmentally induced mutations during the many divisions of apical meristem cells that precede differentiation into gamete-producing tissues and to ensure accurate and productive meiosis. The specific aims of this proposal are: 1) To investigate special properties of Arabidopsis MSH7 protein. DNA substrate specificities of atMsh7.atMsh2 vs atMsh6.atMsh2 protein heterodimers and the steady-state levels of atMSH7 mRNA vs levels expressed by other Arabidopsis MSH and MLH genes in vegetative and putative germ-line tissues will be compared. 2) To analyze MSLH protein roles in prevention of mitotic DNA replication errors and UV mutagensis. 3) To study MSLH protein functins in plant meiosis. Plants are of necessity exposed to sunlight and consequently must have effective DNA repair systems. This work should produce results that will add to our knowledge base but will also be of value to plant breeders and to individuals seeking to genetically engineer plants and to propagate plant cells in culture.