|ALI, SHAWKAT - Universite De Sherbrooke|
|MAGNE, MAXIM - Universite De Sherbrooke|
|CHEN, SHIYAN - Cornell University|
|OBRADOVIC, NATASA - Universite De Sherbrooke|
|JAMSHAID, LUBNA - Universite De Sherbrooke|
|BELAIR, GUY - Agri Food - Canada|
|MOFFETT, PETER - Universite De Sherbrooke|
Submitted to: Frontiers in Plant Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/27/2015
Publication Date: 8/11/2015
Citation: Ali, S., Magne, M., Chen, S., Obradovic, N., Jamshaid, L., Wang, X., Belair, G., Moffett, P. 2015. Analysis of Globodera rostochiensis effectors reveals conserved functions of SPRYSEC proteins in suppressing and eliciting plant immune responses. Frontiers in Plant Science. 6:623.
Interpretive Summary: The potato cyst nematode Globodera rostochiensis (golden nematode) is a worldwide recognized quarantine pest that infects potato. This devastating potato pest injects a variety of effector proteins, including a family of SPRYSEC proteins, into root cells in order to establish successful infection. In this study, we tested the properties of six G. rostochienisis SPRYSEC proteins by expressing them in tobacco leaves. We found that all the six SPRYSEC proteins could suppress plant defenses. Interestingly one of the SPRYSEC effectors (GrSPRYSEC-15) could induce a defense response in tobacco leaves, and tobacco was found to be resistant to a virus expressing GrSPRYSEC-15. These results suggest that SPRYSEC proteins have different functions. A better understanding of the function of this important SPRYSEC family will uncover the molecular details of golden nematode infection of potato.
Technical Abstract: Potato cyst nematodes (PCNs), including Globodera rostochiensis (Woll.), are important pests of potato. Plant parasitic nematodes produce multiple effector proteins, secreted from their stylets, to successfully infect their hosts. These include proteins that are delivered to the apoplast, as well as to the host cytoplasm. A number of effectors from G. rostochiensis predicted to be delivered to be cytoplasmic have been identified, including several belonging to the secreted SPRY domain (SPRYSEC) family of proteins. SPRYSEC proteins are unique to members of the genera Globodera and have been implicated in both the induction and the repression of host defense responses. We have tested the properties of six different G. rostochiensis SPRYSEC proteins by expressing them in Nicotiana benthamiana and N. tabacum. We find that all SPRYSEC proteins tested were able to suppress defense responses induced by NB-LRR proteins as well as cell death induced by elicitors, suggesting that defense repression is a common characteristic of members of this effector family. At the same time, GrSPRYSEC-15 elicited a defense response in N. tabacum, and tobacco was found to be resistant to a virus expressing GrSPRYSEC-15. These results suggest that SPRYSEC proteins may possess characteristics that allow them to be recognized by the plant immune system.