Identification of the WRKY Group I Genes and the Functional Analysis of GhWRKY138 in Cotton Pigment Gland Development

Background: WRKY transcription factors have various functions in leaf senescence, plant maturation, adaptation to stress and regulation of secondary metabolism. However, the relationship between WRKY family and cotton pigment gland development remains unclear. Result In this study, 36 WRKY group I genes were identified in G. hirsutum L . Expression pattern analysis showed that GhWRKY138 of WRKY group I had a large difference in expression between glanded and glandless plants. Virus-induced gene silencing experiments showed that the number of glands decreased significantly with gene silencing. At the same time, we found that the expression of GhMYC2-like , a key gene regulating pigment gland development, also decreased with the decrease of GhWRKY138 . Conclusion GhWRKY138 may involved in the formation and development of cotton glands. This study explored the possible relationship between the WRKY transcription factor family and gland development, which further enriched the connotation of the biological function of WRKY genes. These studies provide new insights into the mechanism of gland development.