Characterization of the C2H2 Zinc Finger Protein Family in Setosphaeria turcica

C2H2 zinc finger (C2H2-ZF) transcription factors, characterized by the presence of a conserved ZnF-C2H2 domain, are widespread among plant-pathogenic fungi such as Magnaporthe oryzae, Fusarium graminearum, and Sclerotinia sclerotiorum and have critical roles in the regulation of fungal growth, development, stress adaptation, and secondary metabolism. However, little is known about the presence and roles of C2H2-ZF transcription factors in Setosphaeria turcica (syn. Exserohilum turcicum), the causal agent of northern corn leaf blight. To address this gap, we identified the complete set of C2H2-ZF transcription factors in the S. turcica genome and characterized their structural characteristics, physicochemical properties, and protein–protein interaction network. We then used RNA sequencing to profile their expression dynamics during fungal development and host infection. The 27 S. turcica C2H2-ZF proteins were classified into three major subfamilies and contained six conserved motifs. All 27 genes were transcribed during 5 stages of fungal development, and 24 were expressed during the infection of susceptible maize, suggesting that they function in both fungal growth and pathogenesis. This study represents the first systematic characterization of C2H2-ZF proteins in S. turcica, offering insight into their potential roles in pathogenicity and establishing a foundation for future functional studies of individual family members.