Arabidopsis Histone Deacetylase 5 is Required for Pseudomonas‐Induced Deacetylation of Histone H3 at Lysine 9

Abstract

The gram‐negative plant pathogen Pseudomonas syringae pv. tomato DC3000 (Pto DC3000) depends on a type III secretion system (T3SS) to colonize plant tissue, and cause disease. The T3SS facilitates injection of virulence proteins called effector proteins (T3Es) directly into host cells. The T3Es have been shown to target components of plant immunity and are essential for Pto to cause disease. We have been interested in determining the extent that Pto T3Es are involved in modulating host chromatin to favor pathogenesis. Through Immunoblot and Chromatin Immunoprecipitation analyses we found a rapid deacetylation of host histone H3 lysine 9 (H3K9) along innate immunity related genes in response to Pto. This deacetylation was dependent on both T3Es and the host histone deacetylase HDA5. Moreover, Arabidopsis plants lacking HDA5 had an enhanced resistance to Pto infections and produced more callose in response to Pathogen Associated Molecular Pattern exposure. Moreover, through analyses of specific T3E Pto mutants and transient and transgenic expression of specific T3Es, we found that only a small subset of the T3Es are needed for the HDA5‐triggered deacetylation. Collectively our data show a Pto T3E‐induced deacetylation by HDA5 along immunity related genes in Arabidopsis.Support or Funding InformationThis work was supported by NSF award #1557417, NSF award # 0940177 and NIGMS award # 8P20GM103427This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.