A MADS‐box transcription factor MoMcm1 is required for male fertility, microconidium production and virulence in Magnaporthe oryzae

Abstract

SummaryAppressorium formation is a key step in the infection cycle of Magnaporthe oryzae. Mst12 is a transcription factor essential for appressorium penetration and invasive growth. In this study we used the affinity purification approach to identify proteins that physically associate with Mst12. One of the Mst12-interacting genes identified was MoMCM1, which encodes a MADS-box protein orthologous to yeast Mcm1. MoMcm1 interacted with both Mst12 and Mata-1 in yeast two-hybrid assays. Deletion of MoMCM1 resulted in the loss of male fertility and microconidium production. The Momcm1 mutant was defective in appressorium penetration and formed narrower invasive hyphae, which may be responsible for its reduced virulence. In transformants expressing MoMCM1-eGFP fusion, GFP signals were observed in the nucleus. We also generated the Momcm1 mst12 double mutant, which was defective in penetration and non-pathogenic. On hydrophilic surfaces, germ tubes produced by the double mutant were severely curved, and 20% of them formed appressoria. In contrast, the Momcm1 or mst12 mutant did not form appressoria on hydrophilic surfaces. These results suggest that MoMCM1 and MST12 have overlapping functions to suppress appressorium formation under non-conducive conditions. MoMcm1 may interact with Mst12 and MatA-1 to regulate germ tube identity and male fertility respectively.

The role of MADS-box transcription factors in secondary metabolism and sexual development in the maize pathogen Fusarium verticillioides

“…MADS-box TFs are involved in a wide array of biological activities (Shore & Sharrocks, 1995 Nolting & Pöggeler, 2006a, b;Zhou et al, 2011). Studies of Sacch.…”

“…MoMcm1, an orthologue of F. verticillioides Mads1 and U. maydis Umc1, has been characterized in M. grisea, and it was demonstrated that the mutant is delayed in appressorium formation, and thus is defective in penetration and colonization of the host (Zhou et al, 2011). Additionally, M. grisea Mig1, an orthologue of F. verticillioides Mads2, has been shown to help the fungus overcome plant defences upon colonization.…”

Abiotic Stress Resistance, a Novel Moonlighting Function of Ribosomal Protein RPL44 in the Halophilic Fungus Aspergillus glaucus

“…strain KRS101 affords cycloheximide resistance to strains, serving as a novel selection marker (39). The present M. oryzae transformants were selected with a high concentration of hygromycin B or phleomycin D1 (Zeocin) (40), both of which are toxic and expensive. In our research, we might use RPL44 to create a dominant selectable marker expressed with the aid of native transcriptional and translational machinery, and it is safe in biological transformation.…”

Regulatory network of genes associated with stimuli sensing, signal transduction and physiological transformation of appressorium in Magnaporthe oryzae

“…As a result, the disruption of MoMST 12 in M. oryzae triggered the formation of non-functional appressorium in the ∆ mst 12 strains. The appressorium formed by the defective strains also failed to mobilise the turgor required to physically breach host cuticle for successful invasion (Park et al 2002; Zhou et al 2011). Additional reports showed that the MoMcm1 protein which serves as a downstream target for Pmk1-MAPK equally plays a crucial role in promoting the development of functional appressorium and host penetration.…”

“…Additional reports showed that the MoMcm1 protein which serves as a downstream target for Pmk1-MAPK equally plays a crucial role in promoting the development of functional appressorium and host penetration. Further research demonstrations have shown that MoMcm1 and MoMst12 assume overlapping functions in regulating cell polarity and turgor generation in appressorium (Park et al 2002; Zhou et al 2011). The deletion of MoMCM 1 phenotyping the mst12 mutant produced appressoria unable to penetrate the plant surface effectively.…”