|Lapitan, N L|
Submitted to: Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/1/2004
Publication Date: 10/1/2004
Citation: Hossain, K.G., Kalavacharla, V., Lazo, G.R., Hegstad, J., Wentz, M.J., Simons, K., Gehlhar, S., Rust, J.L., Syamala, R.R., Obeori, K., Suresh, B., Karunadharma, P., Chao, S., Anderson, O.D., Qi, L.L., Gill, B.S., Linkiewicz, A.M., Dubcovsky, J., Akhunov, E.D., Dvorak, J., Miftahudin, Gustafson, J.P., Sidhu, D., Dilbirligi, M., Gill, K.S., Peng, J., Lapitan, N.V., Bermudez-Kandianis, C.E., Sorrells, M.E., Feril, O., Pathan, M.S., Nguyen, H.T., Gonzalez-Hernandez, J.L., Wennerlind, E., Anderson, J.A., Fenton, D., Close, T.J., Mcguire, P.E., Qualset, C.O., Kianian, S.F. 2004. A chromosome bin map of 2148 est loci of wheat homoeologous group 7. Genetics. 168:687-699. Interpretive Summary: Expressed DNA sequences were taken from 47 cDNA libraries and were physically mapped to specific chromosome regions of wheat group 7 chromosomes. We found that the expressed sequences were not scattered from one end to the other of the group 7 chromosomes, but seemed to be clustered in more distal regions of the chromosomes. This information will be of value to wheat geneticists in map-based cloning of expressed sequences located on wheat group 7 chromosomes.
Technical Abstract: We have mapped 2148 loci representing 919 expressed sequence tag (EST) clones into chromosomes of group 7 of wheat. Regional localization and distribution of these markers directly reflect distribution of gene-rich/poor areas in chromosomes of this group. The individual chromosome deletion maps showed that the average number of loci per unit recombination length in the distal two-third regions of all chromosomes varied from 3 to 6 as compared with proximal regions having ratio of 0.3 to 1. Level of duplicated loci on this group was 55% with more of these loci localized towards the distal region. Expressed sequence tag clones producing three bands on EcoRI-digested DNA blots, not duplicated anywhere else in the genome, and mapping to the three homoeologous chromosomes of group 7, were considered as landmark probes. A consensus chromosome map of group 7 was constructed with 119 landmarks probes. Putative order of these probes in the deletion bins was identified based on corresponding rice BACs/PACs and genetic markers mapped on chromosomes 6 and 8 of rice. Comparative maps of wheat, rice, and barley were produced based on the ordered sequences. Identification of landmarks ESTs and the consensus map provides a framework of conserved coding regions predating the evolution of wheat genomes.