|Lapitan, N L|
Submitted to: Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/1/2004
Publication Date: 10/1/2004
Citation: Miftahudin, Ross, K., Ma, X., Mahmoud, A., Layton, J., Rodriguez, M., Chikmawati, T., Ramalingam, J., Feril, O., Pathan, M.S., Surlan-Momirovic, G., Kim, S., Chema, K., Fang, P., Haule, L., Struxness, H., Birkes, J., Yaghoubian, C., Kinner, R.S., Nguyen, V., Qi, L.L., Linkiewicz, A.M., Dubcovsky, J., Akhunov, E.D., Dvorak, J., Dilbirligi, M., Gill, K.S., Peng, J., Lapitan, N.V., Bermudez-Kandianis, C.E., Sorrells, M.E., Hossain, K.G., Kalavacharla, V., Kianian, S.F., Lazo, G.R., Chao, S., Anderson, O.D., Gill, B.S., Gonzalez, J., Wennerlind, E., Anderson, J.A., Choi, D.W., Fenton, R.D., Close, T.J., Mcguire, P.E., Qualset, C.O., Nguyen, H.T., Gustafson, J.P. 2004. Analysis of est loci on wheat chromosome group 4. Genetics. 168:651-663. Interpretive Summary: Expressed DNA sequences were taken from 26 cDNA libraries and were physically mapped to specific chromosome regions of wheat group 4 chromosomes. We found that the expressed sequences were not scattered from one end to the other of the group 4 chromosomes, but seemed to be clustered in more distal regions of the chromosomes. From our physical map, we were also able to establish the location of group 4 chromosome re-arrangements. This information will be of value to wheat geneticists in map-based cloning of expressed sequences located on wheat group 4 chromosomes.
Technical Abstract: A total of 1918 loci detected by the hybridization of 938 expressed sequence tag unigenes (ESTs) from 26 wheat (Triticum aestivum L. em Thell.) cDNA libraries were mapped to wheat (Chinese Spring) homoeologous group 4 chromosomes using a set of deletion, ditelosomic, and nulli-tetrasomic lines. Of the 1918 EST loci, 786 (41.0 %) mapped to chromosome 4A, 529 (27.6%) mapped to chromosome 4B, and 603 (31.4 %) mapped to chromosome 4D. By comparison, 31.9% of EST loci mapped to the seven chromosomes of the A genome, 35.7% to the B genome, and 32.3% to the D genome. The long arms of all three of the chromosomes contained more EST loci than the short arms. The distal regions of chromosome arms showed higher numbers of EST loci than the proximal regions, with the exception of 4DL. This study confirmed the complex structure of chromosome 4A with the occurrence of two reciprocal translocations involving chromosome arms 4AL, 5AL, and 7BS as previously identified, but also including an additional inversion in the centromeric region of 4A. A consensus EST map for homoeologous group 4 was developed based on 141 unique ESTs. Good co-linearity was shown between the wheat ESTs of homoeologous group 4 and rice (Oryza sativa L.) chromosome 3. Several ESTs also showed some homology with loci on the other rice chromosomes, in particular chromosomes 1, 7, 10, 11, and 12. Limited co-linearity was found between wheat ESTs on homoeologous group 4 and the Arabidopsis genome. Forty-two percent of the homoeologous group 4 ESTs was classified into functional categories.