E-mail: lslht@life.nthu.edu.tw

Reserach

We are interested in rice a-amylase genes regulatory system. Expression of a-amylase genes in rice suspension cells is known to be induced by carbohydrate depletion. The increase of a-amylase synthesis is assumed to accelerate by hyrolysis of cellular starch as an energy source when exogenous carbon source is depleted. Prolonged carbohydrate starvation reduces growth activities of the starved cells and finally lead to cell death. The physiological changes during starvation are similar in plant,animal, and yeast cells. We aim to study the early response of cells to detrimental environment and the mechanistic of growth arrest using carbohydrate-starved cells as a model system. We will isolate cDNA clones which are expressed during early stages of carbohydrate starvation. Some of these clones may be involved in signal transduction pathway and gene regulation. We would also study the expression pattern of several genes isolated from normal and starved cells. We have observed an increase of RNase synthesis in cells during the course of sucrose starvation. Genes encoding the RNase will also be isolated. Studied of the regulation and expression of these genes would lead to a better understanding of the mechanism of growth arrest and cell death in eukaryotes.

Recently, we add okadaic acid (OA) (cytotoxic polyether compound of a C-38 fatty acid first isolated from marine black sponges. It has been demonstrated that OA is a potent inhibitor of protein phosphatases 1 and 2A.) into rice cell culture. After 30 degree, 60 minutes, the mRNA is isolated and performed the Nothern blotting. A intensify hybridization spot is resulted.


Publications

Selected Papers

  1. S.M. Yu, W.S. Tzou, W.S. Lo, H.T. Lee and R. Wu, 1992, Regulation of alpha-amylase-enconding gene expression in germinating seeds and cultured cells of rice. Gene, 122:247-253 (SCI)
  2. Y.C. CHao, H.A. Wood, C.Y. Chang, H.J. Lee, W.C. Shen and H.T. Lee, 1992, Differential expression of Hz-1 baculovirus genes during productive and persistent viral infections. J. Virology, 66: 1442-1448 (SCI)
  3. J.J. Shen, S.P. Jan, H.T. Lee and S.M. Yu, 1994, Control of transcription and mRNA turnover as mechanisms of metabolic repression of alpha-amylase gene expression. Plant J. 5: 655-664 (SCI) Project ID: NSC- - 8-1-0203-B007-501
  4. M.Y. Lue and H.T. Lee, 1994, Poly(A) tail shortening of alpha-amylase mRNAs in vegetative tissues of Oryza Sativa. B.B.R.C., 202: 1031-1037 (SCI)
  5. M.Y. Lue and H.T. Lee, 1994, Protein phosphatase inhibitors enhance the expression of an alpha-amylase gene, alpha-Amy3, in cultured rice cells. B.B.R.C., 205: 807-816 (SCI) Project ID: NSC- - 8-3-0203-B007-024
  6. T.C. Tseng, T.H. Tsai, M.Y. Lue and H.T. Lee, 1995, Identification of sucrose-regulated genes in cultured rice cells using mRNA differential display. Gene, 161: 179-182 (SCI) Project ID: NSC- - 8-4-2311-B0007-020

Conference Papers

  1. M.Y. Lue, K.H. Liu and H.T. Lee, 1995, The mechanism mediating the expression of an aplha-amylase gene, alpha-Amy3, in cultured rice cells, Abstract in the 6th international symposium of society of Chinese bioscientists in America, Vancouver, Canda.