The IRE1/bZIP60 pathway are activated by potexvirus and potyvirus small membrane binding proteins and suppress virus infection
J. VERCHOT (1), D. Halterman (2), O. Arias (1), L. Pena (1), A. VelaArias (3) (1) Oklahoma State University, U.S.A.; (2) USDA/ARS Vegetable Crops Research Unit, U.S.A.; (3) Universidad de las Fuerzas Armadas – ESPE, Quito Ecuador, Ecuador

The endoplasmic reticulum and Golgi network (ERGN) is vital to most cellular biosynthetic processes. Many positive strand RNA viruses depend upon the ERGN for replication, maturation, and egress. Virus infection creates conditions that disrupts the folding capacity of the ER causing stress. We present new data demonstrating that certain ER stress sensors activate the unfolded protein response (UPR), which is signaling cascade that results in changes in host gene expression to aid the cell to adapt to aberrant cellular circumstances and restore homeostasis to the ER. Viruses can cause transient, chronic or acute ER stress and interact with the unfolded protein response (UPR) machinery dictates whether cells become tolerant to infection or achieve a state of unresolvable stress that is marked by cell death. The potexvirus TGB3 movement protein and the potyvirus 6K2 protein both reside in the ER. These proteins stimulate the ER stress sensor IRE1 which splices the bZIP60 mRNA. The truncated bZIP60 transcription factor stimulates expression of ER stress related genes. We determine that the IRE1/bZIP60 pathway contributes to disease regulation and virus systemic infection in plants. This comparative study was undertaken to show that across host species, the UPR pathway responds to downregulate virus accumulation. Complete understanding of these mechanisms will lead to novel strategies to improve plant tolerance to virus infection.

Abstract Number: C11-5, P7-225
Session Type: Concurrent