The innate immune response is the body's first line of defense against pathogen infection. In the June 15th issue of G&D, Dr. Xin Li (University of British Columbia) and colleagues report that three proteins work together in the MOS4-associated complex (MAC) to execute innate immunity in the mustard weed, Arabidopsis.
Dr. Li and colleagues study a plant autoimmune model in which a mutation in one immune receptor, SNC1, causes constitutive activation of the plant's immune response. Dr. Li's group found that 3 key downstream effectors of the SNC1 pathway -- MOS4, AtCDC5 and PRL1 -- are homologous to components of the human spliceosome-associated nineteen complex (NTC). The researchers speculate that the evolutionarily conserved NTC may also play a role in animal innate immunity.
"Our work is further evidence that the little plant Arabidopsis remains a very robust genetic tool for dissecting processes in multicellular eukaryotes, with relevance to the realm of human biology. To our knowledge, this is the first placement of the NTC into a known signaling pathway in any organism. We are continuing to find commonality between animal and plant innate immunity at the level of both receptors and signalling intermediates; the complex we describe, essential for plant innate immunity, may be another example of this."