Identification of TALE Transcription Factor Family and Expression Patterns Related to Fruit Chloroplast Development in Tomato ( L.).

The gene family is an important transcription factor family that regulates meristem formation, organ morphogenesis, signal transduction, and fruit development. A total of 24 genes of the TALE family were identified and analyzed in tomato. The 24 SlTALE family members could be classified into five BELL subfamilies and four KNOX subfamilies. genes were unevenly distributed on every tomato chromosome, lacked syntenic gene pairs, and had conserved structures but diverse regulatory functions. Promoter activity analysis showed that cis-elements responsive to light, phytohormone, developmental regulation, and environmental stress were enriched in the promoter of genes, and the light response elements were the most abundant. An abundance of TF binding sites was also enriched in the promoter of genes. Phenotype identification revealed that the () mutant fruits showed significantly enhanced chloroplast development and chlorophyll accumulation, and a significant increase of chlorophyll fluorescence parameters in the fruit shoulder region. Analysis of gene expression patterns indicated that six genes were highly expressed in the fruit shoulder region, and four genes were highly expressed in the parts with less-developed chloroplasts. The protein-protein interaction networks predicted interaction combinations among these genes, especially between the BELL subfamilies and the KNOX subfamilies, indicating a complex regulatory network of these genes in chloroplast development and green fruit shoulder formation. In conclusion, our result provides detailed knowledge of the gene for functional research and the utilization of the gene family in fruit quality improvement.