Zhongchao YIN received B.S. (1989) from Anhui University, M.S. (1992) from Sun Yat-Sen University and Ph. D. (1997) from Fudan University in China. He then worked for the Institute of Molecular Agrobiology (IMA), Singapore, as a Guest Investigator (1997-1999), a Postdoctoral Research Fellow (1999) and the Head of the Rice Disease Resistance Group (1999-2002). Since August 2002, he has been leading the Molecular Plant Pathology Group at Temasek Life Sciences Laboratory (TLL).
You may wish to contact Dr Zhongchao YIN at:Tel:(65) 6872 7000, 6872 7420 (DID) or 6872 7424 (lab)
For information on PhD studies at TLL, click HERE
- Rice bacterial blight disease
- Molecular breeding of rice
- Genetic engineering of Jatropha curcas
Molecular interaction between rice and Xanthomonas oryzae pv. oryzae
Bacterial blight of rice (Oryza sativa), caused by Xanthomonas oryzae pv. oryzae (Xoo), is a prominent disease throughout the major rice growing regions. During infection, Xoo strains deliver AvrBs3-like effectors, also referred to as transcription activator–like (TAL) effectors, into host cells via the bacterial type III secretion system. TAL effectors function as transcriptional factors and induce expression of specific host genes within the host cells, which facilitate bacterial infection and promote diseases. The recognition specificity between TAL effectors and the targeted host genes are determined by the repetitive central region of each effector, which consists of near-perfect direct repeats of 33- to 34-amino acid residues, and the effector binding element (EBE) within the promoter of the affected gene. Rice has evolved mechanisms of self-immolation by the adaptation of TAL effector-dependent disease resistance (R) genes, whose expression, unintentionally induced by the TAL effectors, triggers a hypersensitive response.
Using a map-based cloning approach, we have isolated two TAL effector-dependent R genes, Xa10 and Xa27, for bacterial blight resistance. Both R genes contain EBEs (EBEAvrXa10 and EBEAvrXa27) in their promoters that are specifically recognized by AvrXa10 and AvrXa27, respectively. The gene induction depends on basal transcription factor OsTFIIAg5 and the V39E substitution in OsTFIIAg5 greatly attenuates the TAL effector-dependent R gene induction. The expression of Xa10 gene induces cell death in plant and HeLa cells. The Xa10 product XA10 localizes as hexamers in the endoplasmic reticulum (ER) and is associated with ER Ca2+ depletion in plant and HeLa cells. These results indicate that XA10 is an inducible, intrinsic terminator protein that triggers programmed cell death by a conserved mechanism involving disruption of the ER and cellular Ca2+ homeostasis. The Xa27 product XA27 relies on an amino-terminal signal-anchor-like sequence to localize to the apoplast of plant cell for resistance to Xoo, but its biochemical function remains to be determined.
Molecular breeding of rice using marker-assisted selection and a transgenic approach
Apart from basic research on molecular plant pathology, we are also interested in molecular breeding of rice using marker-assisted selection and/or a transgenic approach. The rice varieties that we chose for molecular breeding include elite inbred rice and parental lines of hybrid rice. The traits and genes selected for molecular breeding cover disease resistance to rice bacterial blight (Xa4, Xa21 and Xa27) and rice blast (Pi9), submergence tolerance (Sub1A), semi-dwarf (sd1), aromatic rice (fgr), and insect resistance to brown grass hopper (Bph14), stem borer and leaf folder (Cry1Ab/1Ac). Our goal is to develop new rice varieties with high yield, good quality and multiple resistance or tolerance to biotic and abiotic stress.
Genetic engineering of potential biofuel plant Jatropha curcas L.
Jatropha curcas L. is a poisonous, semi-evergreen shrub that belongs to Euphorbiaceae family. J. curcas mainly grows in tropical and subtropical countries. Compared with other plants, J. curcas is a drought-resistant, non-food plant that can grow in marginal lands. J. curcas seeds contain about 25-40% storage lipids. In recent years, J. curcas has emerged as a potential biofuel plant. However, J. curcas seeds contain toxic products, such as phorbol esters and curcins (type-I ribosome inactivating proteins), which hamper the use of its oil and oil meal. In addition, despite the presence of these toxins in J. curcas leaves and seeds, J. curcas is still attacked by insects, fungi and viruses. We are interested in using transgenic approaches to generate transgenic jatropha plants with resistance to insects as well as to produce curcin-deficient seeds.