ARS | Publication request: Genes encoding a callose synthase and phytochrome A are adjacent to a MAP3Ka-like gene in Beta vulgaris USH20

Submitted to: International Journal of Plant Genomics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 1, 2011
Publication Date: June 1, 2011
Citation: Kuykendall, L.D., Shao, J.Y. 2011. Genes encoding a callose synthase and phytochrome A are adjacent to a MAP3Ka-like gene in Beta vulgaris USH20. International Journal of Plant Genomics. DOI: 10.1155/2011/370548.

Interpretive Summary: For important crop plants, genes with important roles in pathogen defense, stress tolerance and development require indepth analysis in order for molecular approaches to be used for their improvement. In this study, genes adjacent to a gene essential for hereditary disease resistance in sugarbeets were characterized using computational methods. The protein product of phyA detects light availability as an essential first step in mounting an effective defense. Gene clustering, important for coordinating expression, also involves genes whose products (1) activate “hypersensitive response,” or localized cell death, to stop pathogen spread and (2) manufacture a type of biological glue called ‘callose’ that can block or trap invading pathogens. Knowledge about the cluster of core plant genes described for the first time in this report will be used by other scientists to devise new strategies effective for improving disease resistance and enhancing profitability and sustainability of crop production.

Technical Abstract: MAP3Ka encodes a key conserved protein kinase responsible for orchestrating a rapid cascade of cellular events ultimately leading to localized cell death. Hypersensitive response, as it is termed, enables genetically-resistant plants to limit microbial invasion under the right environmental conditions. Since knowledge of close, physically-linked genes is important for genome analysis and possibly for improving disease resistance, systematic DNA sequence analysis, gene annotation and protein BLASTs were performed to identify and characterize genes in close physical proximity to a MAP3Ka-like gene in Beta vulgaris L. H20. Callose synthase (BvCS) and phytochrome A (PhyA) genes were discovered within 50 Kb of MAP3Ka on the same 125 Kb BAC. A new chromodomain-carrying gypsy-like LTR retrotransposon, Bert, which is transcribed from the opposing strand, resides within an intron of the BvCS gene.