title: Plant TRAF Proteins Regulate NLR Immune Receptor Turnover.
abstract: In animals, Tumor necrosis factor receptor-associated factor (TRAF) proteins are molecular adaptors that regulate innate and adaptive immunity, development, and abiotic stress responses. Although gene families encoding TRAF domain-containing proteins exhibit enriched diversity in higher plants, their biological roles are poorly defined. Here, we report the identification of two redundant TRAF proteins, Mutant, snc1-enhancing 13 (MUSE13) and MUSE14, that contribute to the turnover of nucleotide-binding domain and leucine-rich repeat-containing (NLR) immune receptors SNC1 and RPS2. Loss of both MUSE13 and MUSE14 leads to enhanced pathogen resistance, NLR accumulation, and autoimmunity, while MUSE13 overexpression results in reduced NLR levels and activity. In planta, MUSE13 associates with SNC1, RPS2, and the E3 ubiquitin ligase SCF(CPR1). Taken together, we speculate that MUSE13 and MUSE14 associate with the SCF E3 ligase complex to form a plant-type TRAFasome, which modulates ubiquitination and subsequent degradation of NLR immune sensors to maintain their homeostasis.
authors: Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
authors: Shuai
authors: S
authors: Huang
authors: Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, China.
authors: Xuejin
authors: X
authors: Chen
authors: Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
authors: Xionghui
authors: X
authors: Zhong
authors: Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
authors: Meng
authors: M
authors: Li
authors: Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
authors: Kevin
authors: K
authors: Ao
authors: Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
authors: Jianhua
authors: J
authors: Huang
authors: Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4, Canada. Electronic address: xinli@msl.ubc.ca.
authors: Xin
authors: X
authors: Li
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D059748:Proteolysis
chemical_list: D029681:Arabidopsis Proteins; C089426:RPS2 protein, Arabidopsis; C482739:SNC1 protein, Arabidopsis