Abstract Detail

Comparative Genomics/Transcriptomics

Andersen, Ethan [1], Ali, Shaukat [2], Byamukama, Emmanuel [3], Yen, Yang [1], Neupane, Surendra [4], Nepal, Madhav [4].

Evolutionary Conservation of PBS1 Homologs in Family Poaceae.

Plant pathogens produce effectors to interfere with host resistance responses as a way to facilitate infection. Many targets of these effectors regulate the expression of genes associated with defense system. Plants initiate responses when pathogen effectors cleave critical target proteins. Pseudomonas syringae cysteine protease effector Pseudomonas syringae pv. phaseolicola B (AvrPphB) cleaves the Arabidopsis thaliana cytoplasmic kinase protein AVRPPHB SUSCEPTIBLE1 (PBS1) and other PBS1-like (PBL) kinases to interfere with immune signaling. The resistance protein RESISTANCE TO PSEUDOMONAS SYRINGAE5 (RPS5) recognizes the cleavage of PBS1 and initiates a response to the bacterial pathogen. While elucidated in Arabidopsis thaliana, recent literature suggests that grasses, such as wheat, also possess PBS1 homologs that share the cleavage domain utilized by AvrPphB. The objectives of this study were to sequence and compare the cleavage sites of PBS1 homolog genes of both cultivated and wild grass family members. PCR was used to amplify PBS1 homologs, which were then sequenced and analyzed. We found that PBS1 has been evolutionarily conserved throughout Poaceae lineages, specifically the region coding for the cleavage site utilized by AvrPphB effectors. While the role of PBS1 as a regulator of resistance response may not have been retained among these species, a selective advantage was likely present to preserve the function of PBS1 as a target for bacterial effectors.

Related Links:
SDSU Nepal Lab

1 - South Dakota State University, Biology And Microbiology, McFadden Biostress Laboratory, Brookings, SD, 57006, United States
2 - South Dakota State University, Agronomy, Horticulture and Plant Sciences, Seed Technology Lab 113D, Brookings, SD, 57006, United States
3 - South Dakota State University, Agronomy, Horticulture and Plant Sciences, Plant Science Building 107, Brookings, SD, 57006, United States
4 - South Dakota State University, Biology And Microbiology, McFadden Biostress Laboratory, Brookings, SD, 57006, USA

Keywords:
Disease Resistance  
Plant Immunity
Grasses
Decoy
Evolutionary Conservation.

Presentation Type: Poster
Session: P, Comparative Genomics and Transcriptomics
Location: Grand Ballroom - Exhibit Hall/Mayo Civic Center
Date: Monday, July 23rd, 2018
Time: 5:30 PM This poster will be presented at 6:15 pm. The Poster Session runs from 5:30 pm to 7:00 pm. Posters with odd poster numbers are presented at 5:30 pm, and posters with even poster numbers are presented at 6:15 pm.
Number: PGT004
Abstract ID:107
Candidate for Awards:Genetics Section Poster Award