Control of growth factor signalling by MACPF proteins

Genome-Wide Analysis of the Membrane Attack Complex and Perforin Genes and Their Expression Pattern under Stress in the Solanaceae

The Membrane Attack Complex and Perforin (MACPF) proteins play a crucial role in plant development and adaptation to environmental stresses. Heretofore, few MACPF genes have been functionally identified, leaving gaps in our understanding of MACPF genes in other plants, particularly in the Solanaceae family, which includes economically and culturally significant species, such as tomato, potato, and pepper. In this study, we have identified 26 MACPF genes in three Solanaceae species and in the water lily, which serves as the base group for angiosperms. Phylogenetic analysis indicates that angiosperm MACPF genes could be categorized into three distinct groups, with another moss and spikemoss lineage-specific group, which is further supported by the examination of gene structures and domain or motif organizations. Through inter-genome collinearity analysis, it is determined that there are 12 orthologous SolMACPF gene pairs. The expansion of SolMACPF genes is primarily attributed to dispersed duplications, with purifying selection identified as the principal driving force in their evolutionary process, as indicated by the ω values. Furthermore, the analysis of expression patterns revealed that Solanaceae genes are preferentially expressed in reproductive tissues and regulated by various environmental stimuli, particularly induced by submergence. Taken together, these findings offer valuable insights into and a fresh perspective on the evolution and function of SolMACPF genes, thereby establishing a foundation for further investigations into their phenotypic and functional characteristics.

Overexpression of the Arabidopsis MACPF Protein AtMACP2 Promotes Pathogen Resistance by Activating SA Signaling

Immune response in plants is tightly regulated by the coordination of the cell surface and intracellular receptors. In animals, the membrane attack complex/perforin-like (MACPF) protein superfamily creates oligomeric pore structures on the cell surface during pathogen infection. However, the function and molecular mechanism of MACPF proteins in plant pathogen responses remain largely unclear. In this study, we identified an Arabidopsis MACP2 and investigated the responsiveness of this protein during both bacterial and fungal pathogens. We suggest that MACP2 induces programmed cell death, bacterial pathogen resistance, and necrotrophic fungal pathogen sensitivity by activating the biosynthesis of tryptophan-derived indole glucosinolates and the salicylic acid signaling pathway dependent on the activity of enhanced disease susceptibility 1 (EDS1). Moreover, the response of MACP2 mRNA isoforms upon pathogen attack is differentially regulated by a posttranscriptional mechanism: alternative splicing. In comparison to previously reported MACPFs in Arabidopsis, MACP2 shares a redundant but nonoverlapping role in plant immunity. Thus, our findings provide novel insights and genetic tools for the MACPF family in maintaining SA accumulation in response to pathogens in Arabidopsis.