607.255.5710
rjw1@cornell.edu
316 Biotechnology Building
Liberty Hyde Bailey Professor of Molecular Biology and Genetics
Publications | Research | Faculty
Background and Research Focus:
Rice is the staple food for more than half of the world’s population, and its production is a source of income and livelihood for millions of people. In Asia alone, over two billion people obtain 60 to 70 percent of their energy intake from rice and its products. Rice crop yields, however, are often limited by drought or high salinity in the soil.
The current focus of research in my laboratory is to produce transgenic rice plants transformed with agronomically useful genes that would increase tolerance to drought and high salinity. We have succeeded in transforming intact rice cells and regenerated many fertile transgenic rice plants. Gene coding for the following proteins have been used to transform rice cells: LEA3, LEA2, pyrroline-5 carboxylate synthetase, arginine carboxylase, and trehalose-6-P synthase and phosphatase for producing transgenic plants. We have observed that the regenerated transgenic rice plants showed increased tolerance to drought, high levels of salt in the soil and low temperatures. Currently, we are using additional agronomically useful genes, one or several at a time, to transform rice.
In past years, we have made contributions to certain areas of DNA biochemistry and molecular biology. Our development of the first method for determining the nucleotide sequence of DNA was of particular importance. To make sequence analysis possible, we designed a novel location-specific primer-extension strategy in 1970, and determined the complete sequence of the two cohesive ends of lambda phage DNA in 1971. Between 1970 and 1973, we showed that our method can be applied to determine the sequence of any DNA by using synthetic location-specific primers. Our primer-extension strategy was later adopted by F. Sanger (1973 to 1977) in developing a much faster method for sequencing DNA; his work was recognized by a Nobel Prize.
With our collaborator, in 1976 we introduced the method of using synthetic oligonucleotide linkers and adaptors to increase the efficiency of manipulating and cloning blunt-ended DNA. Both linkers and adaptors have been widely used in the construction or expression of synthetic genes, such as those encoding for the human growth hormone and interferons. Over the past 25 years, adaptors have been very widely employed in genetic engineering for constructing many vectors for gene cloning.
In 1991, we identified a strong constitutive promoter from the rice Actin 1 gene. This promoter has since been used by hundreds of scientists worldwide to drive the expression of different genes after transferring into rice, corn, wheat, oat, moss and other plants. In 1998, we and our collaborators produced a composite promoter, ABRC, which is abiotic-stress inducible. This promoter has proven useful in producing stress-inducible gene expression in rice for increasing drought and salt tolerance.
Click here to view Dr. Wu's PubMed listings.
Su, J., Hirji, R., Zhang, L., He, C.-K., Selvaraj, G. and Wu, R. (2006) Evaluation of the stress-inducible production of choline oxidase in transgenic rice as a strategy for producing the stress-protectant glycine betaine. J. Exp. Bot. 57, 1129-1135.
Garg, A.K., Sawers, R.J.H., Wang, H., Kim, J.-K., Walker, J.M., Brutnell, T.P., Parthasarathy, M.V., Vierstra, R.D., and Wu, R. (2006) Light-regulated overexpression of an Arabidopsis phytochrome A gene in rice alters plant architecture and increases grain yield. Planta 223, 627-636.
Su, J. and Wu, R. (2004) Stress-inducible synthesis of proline in transgenic rice confers faster growth under stress conditions than that with constitutive synthesis. Plant Science 166, 941-948.
Garg, A.K., Kim, J.-K., Owens, T.G., Ranwala, A.P., Choi, Y.D., Kochian, L.V. and Wu, R.J. (2002) Trehalose accumulation in rice plants confers high tolerance levels to different abiotic stresses. Proc. Natl. Acad. Sci. USA 99, 15898-15903.
Su, J., Shen, Q., Ho, T.-H.D. and Wu, R. (1998) Dehydration-stress-regulated transgene expression in stably transformed rice plants. Plant Physiol. 117, 913-922.
Duan, X., Li, X., Xue, Q., Abo-El-Saad, M., Xu, D. and Wu, R. (1996) Transgenic rice plants harboring an introduced potato proteinase inhibitor II gene are insect resistant. Nature Biotechnology 14, 494-498.
Xu, D., Duan, X., Wang, B., Hong, B., Ho, T.-H.D. and Wu, R. (1996) Expression of a late embryogenesis abundant protein gene, HVA1, from barley confers tolerance to water deficit and salt stress in transgenic rice. Plant Physiol. 110, 249-257.
Wu, R. (1994) Development of the primer-extension approach: a key role in DNA sequencing. Trends Biochem. Sciences 19, 429-433.
McElroy, D., Blowers, A.D., Jenes, B. and Wu, R. (1991) Construction of expression vectors based on the rice actin 1 (Act1) 5' region for use in monocot transformation. Mol. Gen. Genet. 231, 150-160.
Additional Information:
The following link contains mapping details of DsG8-based anchor lines in rice as supporting information in a manuscript titled "Region-Specific, Indexed, Saturation, Ac/Ds Transposon-Based Mutagenesis in Rice" by Chengkun He, Moul Dey, Zhihong Lin, Faping Duan, Fengling Li and Ray Wu, Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853.
Acknowledgement
We thank Dr. T. Nagamine of the National Institute of Agrobiological Sciences, Japan, for high quality Niponbare rice seeds.
Mapping details of DsG8 insertions of Ds anchor lines in rice