Comprehensive Genome-wide Identification, Characterization, and Expression Analysis of CCHC Zinc Finger Gene Family in Wheat (Triticum aestivum L.)

Background: The CCHC zinc finger proteins (CCHC-ZFPs) are transcription factors that play versatile roles in plant growth, development, and responses to biotic/abiotic stress. However, little is known about the CCHC-ZF genes in bread wheat (Triticum aestivum), an important food crop.Results: In this study, 50 TaCCHC-ZF genes were identified and distributed unevenly on 21 wheat chromosomes. According to the phylogenetic features, the 50 TaCCHC-ZF genes were classified into eight groups with specific motifs and gene structures. 43 TaCCHC-ZF genes were identified as segmentally duplicated genes that formed 36 segmental duplication gene pairs. Additionally, the collinearity analyses between wheat and eight other representative plant species showed that wheat had closer phylogenetic relationships with monocots compared to dicots. A total of 636 cis-elements related to environmental stress and phytohormone responsiveness were identified in the promoter of TaCCHC-ZF genes. Moreover, GO enrichment results revealed that all 50 TaCCHC-ZF genes were annotated under metal ion binding and nucleic acid binding. 91 miRNA binding sites within the 34 TaCCHC-ZF genes were identified by miRNA targets analyses, indicating that the expression of TaCCHC-ZF genes could be regulated by the miRNAs. Based on published transcriptome data, 38 TaCCHC-ZF genes were identified as DEGs, and 15 TaCCHC-ZF genes among them were verified by qRT-PCR assays, which showed response to drought, heat, or simultaneous response of them.Conclusions: This study systematically explored the gene structures, evolutionary characteristics, and potential roles during environmental responses of TaCCHC-ZF genes, providing a foundation for further investigation and application of TaCCHC-ZF genes in the molecular breeding of T. aestivum.