[Gene cloning and biological function of CgRGS2 in Colletotrichum gloeosporioides].

Objective: Regulators of G-protein signaling (RGS) are negative regulatory factors of G protein and play important roles in growth development and pathogenicity of plant pathogen. However, biological functions of RGS in Colletotrichum gloeosporioides have not been studied so far. We cloned an RGS gene of CgRGS2 in C. gloeosporioides and analyzed its biological function.

Methods: Gene CgRGS2 was cloned using PCR and analyzed. The gene-knockout mutant of CgRGS2 was obtained by homologous recombination, and the complementary strain was also built based on the mutant. Biological function of CgRGS2 was determined through phenotypic analysis.

Results: CgRGS2 encoded a 574-amino acids protein, containing an RGS function domain in the N terminal. Comparing to the wild type, the knockout mutant of CgRGS2 had slow growth, thick aerial hyphae, reduced conidia with multi-end germination, sensitive to oxidative stress and SDS, decreased pathogenicity.

Conclusion: Protein CgRGS2 was involved in regulation of vegetative growth, conidium production and germination, oxidative stress response, cell wall integrity and pathogenicity of C. gloeosporioides.