Genome-wide identification and analysis of the MYB transcription factor family in mycoparasite Cladosporium SYC63 strain

Abstract:

[Background] V-myb avian myeloblastosis viral oncogene homolog (MYB) transcription factors, which are ubiquitous in fungi, are vital in stress response and pathogenicity of the microbes. Cladosporium sp., parasitizing rust fungi, is a potential candidate for biocontrol. However, no report of its MYB transcription factors is available. The identification and expression analysis of its MYB transcription factor family are of great significance for understanding role of Cladosporium sp. in mycoparasitism. [Objective] To clarify the number of MYB transcription factors in Cladosporium cladosporioides SYC63 strain and the roles in the mycoparasitism. [Methods] We predicated fundamental characteristics of the MYB transcription factors with bioinformatics methods and analyzed the expression of them in the presence of aecidiospores. [Results] C. cladosporioides SYC63 harbors 22 MYB transcription factor genes and all the MYB transcription factors contain the SANT domain with molecular weight of 28.26–239.05 kDa and pI of 4.57–10.15. They are all hydrophilic proteins and mostly located in the nucleus. These genes can be classified to 1R-MYB and 2R-MYBs, which contain promoter binding sites for the response to pathogens. After rust spore induction, most SycMYBs were down-regulated, and only six genes were up-regulated. Eight genes with high expression or great fold change were selected for RT-qPCR, and the results suggested different change trends of expression after the induction for different time. Among the eight genes, SycMYB6 kept at a high level during the infestation. [Conclusion] MYB transcription factors play a role in the response to infestation and stress resistance of strain SYC63 during the mycoparasitism. The result is expected to lay a theoretical basis for further exploring the role of MYB transcription factor family in fungi and the mycoparasitim mechanism of Cladosporium sp..