暹罗炭疽菌C2H2型转录因子CsCreA参与调控营养生长、胁迫响应、孢子发育及致病性

A C2H2 transcription factor CsCreA regulates vegetative growth, stress responses, conidial development, and pathogenicity of Colletotrichum siamense

摘要:

【背景】暹罗炭疽菌(Colletotrichum siamense)是侵染橡胶的主要病原菌之一，每年造成严重的经济损失。CreA在调控真菌生长及发育过程中发挥着重要作用。【目的】从暹罗炭疽菌中鉴定CreA的同源蛋白CsCreA，并分析其生物学功能。【方法】利用同源重组的方法构建暹罗炭疽菌敲除突变株ΔCscreA和互补菌株，通过测定其营养生长、胁迫因子响应、分生孢子产量及萌发、致病性等明确其功能。【结果】CscreA编码1个含有386个氨基酸的蛋白和2个典型的C2H2蛋白结构域。相较于野生型菌株，敲除突变株ΔCscreA生长速度减慢，并且对H₂O₂和刚果红更加敏感，对KCl敏感性下降；ΔCscreA分生孢子的产量和萌发率显著降低，致病性减弱。【结论】暹罗炭疽菌转录因子CsCreA参与调控菌株营养生长、胁迫响应、分生孢子的产生、萌发和致病过程。

Abstract:

[Background] Colletotrichum siamense is one of the major pathogens infecting rubber trees, causing serious economic losses annually. CreA plays a crucial role in regulating fungal growth and development. [Objective] To identify the homolog of CreA, CsCreA, in C. siamense and analyze its biological functions. [Methods] The knockout mutant ΔCscreA and its complementation strain were constructed by homologous recombination. The roles of CsCreA in vegetative growth, stress responses, conidial production and germination, and pathogenicity of C. siamense were characterized. [Results] CscreA encoded a protein composed of 386 amino acid residues and containing two typical C2H2 zinc finger domains. Compared with the wild-type strain, ΔCscreA exhibited slow growth, increased sensitivity to H₂O₂ and Congo red, decreased sensitivity to KCl, significantly reduced conidial production and germination rate, and weakened pathogenicity. [Conclusion] The transcription factor CsCreA is involved in regulating the vegetative growth, stress responses, conidial production and germination, and pathogenicity of C. siamense.