Abstract:

TCP gene is a plant-specific transcription factor, and plays an important role in plant growth and development. The identification of tobacco TCP gene family may provide theoretical basis for the study of tobacco TCP gene function and genetic improvement. Based on the whole genome data of tobacco（Nicotiana tabacum L.）, the tobacco TCP gene family was identified by BLAST, and the physicochemical properties, gene structure, protein domain, chromosome distribution, phylogeny evolution and promoter analysis of the family members were analyzed by bioinformatics. The expressions of TCP gene family in various tissues of different flue-cured tobacco varieties were verified via RT-qPCR. A total of 20 TCP genes were identified in tobacco, and they were divided into two categories, Class I and Class II. The known TCP genes were located on different chromosomes and were unevenly distributed, and all TCP genes had conserved domains. The cis-elements of growth, development and hormone response were significantly enriched in the promoter regions of the TCP gene family, and some TCP genes also had low-temperature stress elements; 20 NtTCP genes were expressed to different degrees in different tissues and leaves of K326 and Ti706, and NtTCP genes were expressed in tobacco K326 and Ti706, and the expressions were tissue-specific. The expressions of subfamily Class I genes were higher in 6 tissues and leaves at seedling stage, while the expressions of subfamily Class II genes were higher in seedling leaves, upper leaves and middle leaves. The results revealed that the members of tobacco TCP gene family play an important role in the growth and development of tobacco, which provides a basis for exploring the biological functions of tobacco TCP gene family.

Key words: tobacco, TCP gene, genome-wide identification, bioinformatics, organizational differences, expression pattern analysis