Location: Plant Science ResearchTitle: A maize polygalacturonase functions as a suppressor of the hypersensitive response and programmed cell death in maize
|HE, YIJAN - North Carolina State University|
|KARRE, SHAILESH - North Carolina State University|
|JOHAL, GURI - Purdue University|
Submitted to: BMC Plant Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/1/2019
Publication Date: 8/1/2019
Citation: He, Y., Christensen, S.A., Karre, S., Johal, G., Balint Kurti, P.J. 2019. A maize polygalacturonase functions as a suppressor of the hypersensitive response and programmed cell death in maize. Biomed Central (BMC) Plant Biology. 19:310.
Interpretive Summary: In this manuscript we show that a a polygalacturonase enzyme, which is predicted to be involved in degradation of pectin, also acts as a suppressor of programed cell death, specifically a form of programed cell death during the defense response known as the hypersensitive response.
Technical Abstract: The hypersensitive defense response (HR) in plants is a rapid, localized cell death response around the point of attempted pathogen penetration. HR is usually triggered by a pathogen recognition event mediated by a nucleotide-binding site, leucine-rich repeat (NLR) gene. The autoactive maize NLR resistance gene Rp1-D21 confers a spontaneous HR response in the absence of pathogen recognition. Previous work identified a set of loci associated with variation in the severity of Rp1-D21-induced HR. A polygalacturonase gene homolog, here termed ZmPGH1, was identified as a possible causal gene at one of these loci on chromosome 7. We show here that expression of ZmPGH1 can inhibit the HR-inducing activity of Rp1-D21 and that of another autoactive NLR, RPM1(D505V), in a transient expression assay system in Nicotiana benthamiana. Using a transposon insertion line we show that overexpression of ZmPGH1 in maize is associated with suppression of chemically-induced programmed cell death but that it had no discernable effect on resistance to two foliar fungal pathogens.