Genome-wide identification of members of the TCP gene family in switchgrass (Panicum virgatum L.) and analysis of their expression.

Teosinte branched 1/Cycloidea/Proliferating cell factor 1 (TCP) proteins belongs to a plant-specific transcription factor family that plays important roles in plant development. TCP gene-regulated plant branching occurs downstream in the strigolactone pathway. In this study, 41 TCP genes were identified in the genome of Panicum virgatum L. (switchgrass). These genes all contained the TCP conserved domain, and they belonged to two subfamilies distributed across 18 chromosomes. Analysis of gene expression using RNA-Seq data showed that 16 TCP genes were highly expressed in the inflorescence and shoot. The expression patterns of 13 selected PvTCP genes were analyzed in different tissues, and their responses to strigolactones (SLs) were examined. The selected genes were expressed differentially in a range of tissues and to application of SLs, indicating that PvTCPs were involved in a range of developmental and physiological processes. This genome-wide analysis and determination of PvTCP gene-expression patterns yielded valuable information on switchgrass development that will inform studies into improving switchgrass and other species for crop production.