Fusarium head blight (FHB), caused by Fusarium graminearum, poses a significant threat to the yields of wheat and other crops, as well as to food security.Small secreted cysteine-rich proteins (SSCRPs) play a crucial role in the infection process of plant pathogens.Nevertheless, their functions in F.graminearum have not been previously reported.In this study, through homologous recombination and polyethylene glycol (PEG) mediated protoplast transformation, the knockout mutant (ΔFGSG_10443) of the SSCRP-coding gene FGSG_10443 and its complementation strain were obtained.Phenotypic analysis revealed that compared to the wild type and the complementation strains, ΔFGSG_10443 exhibited no significant differences in vegetative growth, sexual reproduction, and deoxynivalenol production;however, the conidial production was reduced by 30.13%.Environmental stress assays demonstrated that the ΔFGSG_10443 mutant exhibited increased sensitivity to sodium dodecyl sulfate and H2O2.Pathogenicity assays indicated a significant reduction in the virulence of ΔFGSG_10443 on wheat heads and coleoptiles.Compared with the wild type and complementation strains, the disease incidence of wheat heads and the lesion length of coleoptiles decreased by 70.05% and 66.24%, respectively.Collectively, these findings suggest that FGSG_10443 is involved in the conidial production, responses to environmental stresses, and the pathogenicity of F.graminearum.Nonetheless, the specific mechanism of action still requires further investigation.
[1] GUO L, ZHAO G Y, XU J R, et al.Compartmentalized gene regulatory network of the pathogenic fungus Fusarium graminearum[J].New Phytologist, 2016, 211(2):527-541.
[2] PAUDEL B, PEDERSEN C, YEN Y, et al.Fusarium graminearum virus-1 strain FgV1-SD4 infection eliminates mycotoxin deoxynivalenol synthesis by Fusarium graminearum in FHB[J].Microorganisms, 2022, 10(8):1484.
[3] CHEN Y, WANG J, YANG N, et al.Wheat microbiome bacteria can reduce virulence of a plant pathogenic fungus by altering histone acetylation[J].Nature Communications, 2018, 9:3429.
[4] WANG W J, DENG Z H, WU H Y, et al.A small secreted protein triggers a TLR2/4-dependent inflammatory response during invasive Candida albicans infection[J].Nature Communications, 2019, 10:1015.
[5] 韩长志, 许僖.植物病原丝状真菌分泌蛋白及CAZymes的研究进展[J].南京林业大学学报(自然科学版), 2017, 41(5):152-160.
HAN C Z, XU X.Advance in functional research of secreted protein and CAZymes in plant pathogenic filamentous fungus[J].Journal of Nanjing Forestry University (Natural Sciences Edition), 2017, 41(5):152-160.
[6] WANG D, TIAN L, ZHANG D D, et al.Functional analyses of small secreted cysteine-rich proteins identified candidate effectors in Verticillium dahliae[J].Molecular Plant Pathology, 2020, 21(5):667-685.
[7] SHU X Y, XU D Z, JIANG Y Q, et al.Functional analyses of a small secreted cysteine-rich protein ThSCSP14 in Tilletia horrida[J].International Journal of Molecular Sciences, 2022, 23(23):15042.
[8] WANG J, WANG D, JI X B, et al.The Verticillium dahliae small cysteine-rich protein VdSCP23 manipulates host immunity[J].International Journal of Molecular Sciences, 2023, 24(11):9403.
[9] LU S W, EDWARDS M C.Genome-wide analysis of small secreted cysteine-rich proteins identifies candidate effector proteins potentially involved in Fusarium graminearum-wheat interactions[J].Phytopathology, 2016, 106(2):166-176.
[10] WANG G H, WANG C F, HOU R, et al.The AMT1 arginine methyltransferase gene is important for plant infection and normal hyphal growth in Fusarium graminearum[J].PLoS One, 2012, 7(5):e38324.
[11] 钱沈安, 胡政, 于伊楠, 等.1-辛烯-3-醇对禾谷镰刀菌的抑制活性及作用机理[J].食品科学, 2023, 44(18):93-101.
QIAN S A, HU Z, YU Y N, et al.Inhibition activity and mechanism of 1-octen-3-ol on the growth and deoxynivalenol biosynthesis of Fusarium graminearum[J].Food Science, 2023, 44(18):93-101.
[12] WERNET N, WERNET V, FISCHER R.The small-secreted cysteine-rich protein CyrA is a virulence factor participating in the attack of Caenorhabditis elegans by Duddingtonia flagrans[J].PLoS Pathogens, 2021, 17(11):e1010028.
[13] DU Z Z, WENG H, JIA H Y, et al.Characterization of a small cysteine-rich secreted effector, TcSCP9014, in Tilletia controversa[J].Plants, 2024, 13(11):1523.
[14] ZHANG N, YANG J Y, FANG A F, et al.The essential effector SCRE1 in Ustilaginoidea virens suppresses rice immunity via a small peptide region[J].Molecular Plant Pathology, 2020, 21(4):445-459.
[15] SEITNER D, UHSE S, GALLEI M, et al.The core effector Cce1 is required for early infection of maize by Ustilago maydis[J].Molecular Plant Pathology, 2018, 19(10):2277-2287.
[16] KUMAR R, MUKHERJEE P K.Trichoderma virens Alt a 1 protein may target maize PR5/thaumatin-like protein to suppress plant defence:An in silico analysis[J].Physiological and Molecular Plant Pathology, 2020, 112:101551.
[17] WANG W F, AN B, FENG L P, et al.A Colletotrichum gloeosporioides cerato-platanin protein, CgCP1, contributes to conidiation and plays roles in the interaction with rubber tree[J].Canadian Journal of Microbiology, 2018, 64(11):826-834.
[18] AN B, WANG W F, GUO Y F, et al.Bas2 is required for conidiation and pathogenicity of Colletotrichum gloeosporioides from Hevea brasiliensis[J].International Journal of Molecular Sciences, 2018, 19(7):1860.
[19] CHEN X R, LI Y P, LI Q Y, et al.SCR96, a small cysteine-rich secretory protein of Phytophthora cactorum, can trigger cell death in the Solanaceae and is important for pathogenicity and oxidative stress tolerance[J].Molecular Plant Pathology, 2016, 17(4):577-587.
[20] HONG X F, QI F, WANG R, et al.Ascorbate peroxidase 1 allows monitoring of cytosolic accumulation of effector-triggered reactive oxygen species using a luminol-based assay[J].Plant Physiology, 2023, 191(2):1416-1434.
[21] GAO M J, HE Y, YIN X, et al.Ca2+ sensor-mediated ROS scavenging suppresses rice immunity and is exploited by a fungal effector[J].Cell, 2021, 184(21):5391-5404.e17.
[22] WU C X, CHEN H L, YUAN M Y, et al.FgAP1σ is critical for vegetative growth, conidiation, virulence, and DON biosynthesis in Fusarium graminearum[J].Journal of Fungi, 2023, 9(2):145.
[23] XU Q, HU S, JIN M X, et al.The N-terminus of a Fusarium graminearum-secreted protein enhances broad-spectrum disease resistance in plants[J].Molecular Plant Pathology, 2022, 23(12):1751-1764.
[24] JIN M X, HU S, WU Q, et al.An effector protein of Fusarium graminearum targets chloroplasts and suppresses cyclic photosynthetic electron flow[J].Plant Physiology, 2024, 196(4):2422-2436.
[25] JIANG C, HEI R N, YANG Y, et al.An orphan protein of Fusarium graminearum modulates host immunity by mediating proteasomal degradation of TaSnRK1α[J].Nature Communications, 2020, 11:4382.
