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 Our group is interested in plant secondary metabolism and cotton biology. Current research includes investigation of terpene biosynthesis, plant secondary metabolism and plant-insect interactions, plant-mediated insect RNA interference, and cotton fiber development.
Lab Homepage: http://sippe.ac.cn/xy。
Principal Investigator: Dr. Chen, Xiao-Ya, Professor, Academician. Email: xychen@sibs.ac.cn
Staff: Ling-Jian Wang, Dr. Ying-Bo Mao, Research Associate Professors; Dr. Chang-Qing Yang, Xiu-Ming Wu, Research Assistant Professors; Zhi-Ping Lin, Technician (emeritus)
 Postdoctoral Associates: Dr. Xin Fang; Dr. Xiao-Xia Shangguan
Graduate Students: Bing Xu; Gao-Jie Hong; Jian-Xu Li; Wen-Juan Cai; Xue-Yi Xue; Xiao-Yuan Tao; Chun-Min Shan; Zhong-Xia Yu; Xiang Gao; Lu-Men Chao; Ju-Xin Ruan; Bo Zhao; Hui Hong
Graduated Students: Nan Yu (2005, PhD); Chang-Qing Yang (2005, PhD)
Cotton Plants Expressing DsCYP6AE14 Show Enhanced Resistance to Bollworms
Gossypol, a sesquiterpene aldehyde present in cotton plants, plays an important role in cotton defense against herbivores and pathogens. We are interested in elucidation of gossypol biosynthesis pathway. Previously, we isolated a gossypol inducible P450 from bollworm (Helicoverpa armigera), CYP6AE14, and generated Arabidopsis and tobacco plants expressing the double stranded RNA (dsRNA) targeting this bollworm’s P450 gene. The bollworms fed on the transgenic dsCYP6AE14 plants showed suppressed CYP6AE14 expression and reduced growth on gossypol-containing diet (Mao et al., 2007). We then generated the dsRNA-expressing cotton (Gossypium hirsutum) plants. Bollworm larvae reared on T2 plants of the ds6-3 line exhibited drastically retarded growth, and the transgenic plants were less damaged by bollworms than the control. Quantitative RT-PCR showed that the CYP6AE14 expression level was reduced in the larvae. These results demonstrate that RNAi technology can be used for engineering insect-proof cotton cultivar.
Temporal Control of Trichome Distribution by miR156-Targeted SPL Genes in Arabidopsis thaliana
In Arabidopsis thaliana, the distribution of trichome cells is spatially and temporally regulated. We found that microRNA156-tageted SPL (SQUMOSA PROMOTER BINDING PROTEIN LIKE) genes temporally control the trichome distribution on inflorescence stems and floral organs. Plants over-expressing miR156 (p35S::MIR156f) developed ectopic trichomes on the stem and floral organs, by contrast, plants having elevated levels of SPLs produced fewer trichomes. During plant development the increase of SPL9 transcript levels coordinates with the gradual loss of trichomes on stems and flowers. The single MYB transcription factor genes TRICHOMELESS 1 (TCL1) and TRIPTYCHON (TRY) are negative regulators of trichome development. We found that SPL9 represses trichome production by directly activation of TCL1 and TRY expression through binding to their promoters, and this activation is independent of GL1. Both TCL1 and TRY proteins inhibit trichome development by interfering with the binding of GLABROUS 1 (GL1) to GLABROUS (GL3), and subsequently disrupting the formation of GL1-GL3-TTG transcription complex. Stabilization of this complex by a fusion protein of GL1 resulted in production of ectopic trichomes in the florescence and floral organs. Our results reveal that the miR156-regulated SPLs provide a direct link between developmental programming and trichome distribution.
Major Publications:
Yu N, Cai WJ, Wang S, Shan CM, Wang LJ, Chen XY*. (2010) Temporal control of trichome distribution by miR156-targeted SPL genes in Arabidopsis thaliana. The Plant Cell 22: 2322-2335 Mao YB, Tao XY, Xue XY, Wang LJ, Chen XY*. (2010) Cotton plants expressing CYP6AE14 double-stranded RNA show enhanced resistance to bollworms. Transgenic Research doi:10.1007/s11248-010-9450-1 Yang CQ, Lu S, Mao YB, Wang LJ, Chen XY*. (2010) Characterization of two NADPH: Cytochrome P450 reductases from cotton (Gossypium hirsutum). Phytochemistry 71: 27-35 Wang L, Li XR, Lian H, Ni DA, He YK, Chen XY, Ruan YL*. (2010) Evidence that high activity of vacuolar invertase is required for cotton fiber and Arabidopsis root elongation through osmotic dependent and independent pathway, respectively. Plant Physiology 154: 744-756 Shangguan XX, Yu N, Wang LJ, Chen XY*. (2010) Recent advances in molecular biology research on cotton fiber development. In: Cotton (U.B. Zehr, ed.); Biotechnology in Agriculture and Forestry 65: Chapter 9, 161-175
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