The rapid evolution of complex disease resistance loci in plants.
Plants have many disease resistance genes that initiate a signal transduction cascade of antimicrobial factors after the pathogen signal is recognized. Many of these resistance genes are highly complex and highly unstable, often in ways that are comparable to events seen at the immunoglobin and histocompatibility genes of chordates. We are studying one of these genes, Rp1 of maize, in significant detail. We have sequenced the entire complex of more than 650 kb. We are now characterizing gene expression, gene function, and the mechanisms of hyper-evolution in this cluster. In addition, we are studying and isolating other disease resistance genes from maize and sorghum. These new resistance genes will provide an interesting comparison to the Rp1 complex and may also prove useful for crop improvement.
Recent related publications :
Nagy ED, Lee TC, Ramakrishna W, Xu Z, Klein PE, SanMiguel P, Cheng CP, Li J, Devos KM, Schertz K, Dunkle L, Bennetzen JL. (2007) Fine mapping of the Pc locus of Sorghum bicolor, a gene controlling the reaction to a fungal pathogen and its host-selective toxin. Theor Appl Genet. 114(6):961-70. Pub Med Link
Chu Z, Fu B, Yang H, Xu C, Li Z, Sanchez A, Park YJ, Bennetzen JL, Zhang Q, Wang S (2006) Targeting xa13, a recessive gene for bacterial blight resistance in rice. Theor Appl Genet. 112(3):455-61. Pub Med Link
Chu Z, Yuan M, Yao J, Ge X, Yuan B, Xu C, Li X, Fu B, Li Z, Bennetzen JL, Zhang Q, Wang S. (2006) Promoter mutations of an essential gene for pollen development result in disease resistance in rice. Genes and Dev. 20(10):1250-5 Pub Med Link
Ramakrishna, W., J. Emberton , P. SanMiguel , M. Ogden, V. Llaca , J. Messing, and J. L. Bennetzen (2002) Comparative sequence analysis of the sorghum rph region and the maize rp1 resistance gene complex. Plant Physiol 130:1728-1738. Pub Med link
Ramakrishna, W., J. Emberton , M. Ogden, P. SanMiguel and J. L. Bennetzen (2002) Structural analyses of the maize Rp1 complex reveals numerous sites and unexpected mechanisms of local rearrangement. Plant Cell 14:3213-3223. Pub Med link