HISTONE MONOUBIQUITINATION1 interacts with a subunit of the mediator complex and regulates defense against necrotrophic fungal pathogens in Arabidopsis

Rahul Dhawan, Hongli Luo, Andrea Maria Foerster, Synan Abuqamar, Hai Ning Du, Scott D. Briggs, Ortrun Mittelsten Scheid, Tesfaye Mengiste

Research output: Contribution to journalArticlepeer-review

186 Citations (Scopus)

Abstract

This work examines the role of the Arabidopsis thaliana RING E3 ligase, HISTONE MONOUBIQUITINATION1 (HUB1) in disease resistance. Loss-of-function alleles of HUB1 show increased susceptibility to the necrotrophic fungal pathogens Botrytis cinerea and Alternaria brassicicola, whereas HUB1 overexpression conferred resistance to B. cinerea. By contrast, responses to the bacterial pathogen Pseudomonas syringae are unaltered in hub1 plants. hub1 mutants have thinner cell walls but increased callose around an infection site. HUB1 acts independently of jasmonate, but ethylene (ET) responses and salicylate modulate the resistance of hub1 mutants to necrotrophic fungi. The ET response factor ETHYLENE INSENSITIVE2 is epistatic to HUB1 for A. brassicicola resistance but additive to HUB1 for B. cinerea resistance. HUB1 interacts with MED21, a subunit of the Arabidopsis Mediator, a conserved complex that regulates RNA polymerase II. RNA interference lines with reduced MED21 expression are highly susceptible to A. brassicicola and B. cinerea, whereas T-DNA insertion alleles are embryonic lethal, suggesting an essential role for MED21. However, HUB1-mediated histone H2B modification is independent of histone H3 and DNA methylation. In sum, histone H2B monoubiquitination is an important chromatin modification with regulatory roles in plant defense against necrotrophic fungi most likely through modulation of gene expression.

Original languageEnglish
Pages (from-to)1000-1019
Number of pages20
JournalPlant Cell
Volume21
Issue number3
DOIs
Publication statusPublished - Mar 2009
Externally publishedYes

ASJC Scopus subject areas

  • Plant Science
  • Cell Biology

Fingerprint

Dive into the research topics of 'HISTONE MONOUBIQUITINATION1 interacts with a subunit of the mediator complex and regulates defense against necrotrophic fungal pathogens in Arabidopsis'. Together they form a unique fingerprint.

Cite this