TcCYS4, a cystatin from cocoa, reduces necrosis triggered by MpNEP2 in tobacco plants

• DOI: 10.4238/2014.september.26.1
• Publication Date: 2014-09-29T11:25:30Z
• Authors: L.S. Santana; M.G.C. Costa; N.M. Pirovani; A.F. Almeida; F.C. Alvim; C.P. Pirovani
• Keywords: Cystatin; Cysteine protease; Hypersensitive response

In Brazil, most cocoa bean production occurs in Southern Bahia. Witches' broom disease arrived this area 1989 and has since caused heavy losses production. The is by the basidiomycete fungus Moniliophthora perniciosa, a hemibiotrophic that produces necrosis ethylene-inducting protein (MpNEP2) during infection; can activate cysteine proteases induce programmed cell death. Cysteine be modulated cystatin. study, we overexpressed TcCYS4, cystatin, tobacco plants evaluated effect on MpNEP2 model plants. Tccys4 cDNA was cloned into pCAMBIA 1390 vector inserted via Agrobacterium tumefaciens. Transgene expression analyzed reverse transcription-quantitative PCR Western blot analysis. Transcript levels Tcccys4:tobacco lines were 8.9- 1.5-fold higher than wild-type (wt). showed no change growth compared to wt CO2 net assimilation (A) increased Only one line statistically significant stomatal conductance (gs) transpiration rate (E) changes. infiltered foliar mesophyll of plants, necrotic lesions attenuated highly expressing Tccys4. Our results suggest cystatin TcCYS4 affects activity related progression death This may occur through action inhibit activated plant tissues. Further studies are necessary examine Theobroma cacao-M. perniciosa pathosystem.