Functional characterization of the CYSTEINE DESULPHURASE (CD) gene involved in nonhost disease resistance
J. FONSECA (1), S. Lee (2), S. Muthappa (3), K. Mysore (4) (1) Noble Foundation, U.S.A.; (2) University of Florida, U.S.A.; (3) NIPGR, India; (4) Noble Foundation, U.S.A.

Cysteine desulphurase (CD) proteins produce sulfur from cysteine residues that will be used in the assembly of Fe-S cluster biogenesis. A CD homolog in yeast has been shown to be required for Fe–S protein activity but also for iron metabolism regulation.  Here we investigate the role of CD in plant defense, more specifically in nonhost disease resistance. Using virus-induced gene silencing (VIGS) followed by nonhost pathogen infection (Pseudomonas syringae pv. tomato T1 and Pseudomonas syringae pv. glycinea) in Nicotiana benthamiana we showed that the NbCD silenced plants were more susceptible to nonhost pathogen infection than non-silenced control plants. Additionally, NbCD silenced plants exhibited stunted growth and leaf lesion phenotype similar to previously reported AtNFS1 (homolog of NbCD) silenced Arabidopsis. Expression of a glutamyl-tRNA reductase enzyme coding gene (HEMA1), that catalyze the production of 5-aminolevulinic acid (ALA), was found to be downregulated in the NbCD silenced plants in comparison to control indicating that NbCD may indeed play a role in the heme biosynthesis pathway. We shall report further characterization of CD and its role in plant defense against bacterial pathogens. 

Abstract Number: P18-669
Session Type: Poster