Unraveling a growth-promoting potential for plants: Genome-wide identification and expression state of the TCP gene family in Juglans mandshurica

• TCP genes from Juglans mandshurica ( JmTCPs ) were identified. • JmTCP12 and JmTCP29 were differentially expressed in walnut exocarp, seed kernel, male and female flower. • JmTCP23, JmTCP30, JmTCP24, JmTCP32 , and JmTCP15 had a high homology with AtTCPs , which control of morphogenesis of shoot organs and participated in ovule development. • Transgenic verification experiments confirmed that JmTCP31 can promote plant growth and shorten the flowering period. The TCP gene family stands as a pivotal factor in regulating plant growth, development, and resilience to abiotic stress. Despite extensive research and identification of TCP genes across diverse plant species, the intricate functionality and evolutionary expansion of TCP genes within Juglans mandshurica remain relatively uncharted territories, necessitating thorough investigation. In this work, 35 JmTCP genes belonging to two distinct subfamilies were identified in the genome of J. mandshurica , which were unevenly distributed on 13 chromosomes. To gain insights into structural characteristics, a comprehensive analysis encompassing gene structure was conducted, motif composition, and conserved domain examination. Furthermore, cis -acting element and protein interaction network analyses were leveraged to elucidate potential biological functions associated with these genes. Transcriptome data unveiled that JmTCP12 and JmTCP29 are essential for the development of walnut exocarps, embryos, male and female flowers. Furthermore, the results of the genetic transformation experiments demonstrated that JmTCP31 possesses the capability to significantly promote leaf development and expedite the flowering cycle. Collectively, this study offers novel insights into the molecular mechanisms underlying the TCP gene family's contributions to growth and development in J. mandshurica , enriching understanding of this essential gene family in plants and shedding light on potential applications in agricultural biotechnology.