Identification and expression analysis of LATERAL ORGAN BOUNDARIES DOMAIN (LBD) transcription factor genes in Fragaria vesca

The LATERAL ORGAN BOUNDARIES DOMAIN (LBD) gene family encodes plant-specific transcription factors that play crucial roles in the growth and development in many plant species. However, no systematic study of LBD genes has been conducted in strawberry. In this study, 35 LBD (FvLBD) genes were identified in the diploid woodland strawberry genome (Fragaria vesca L.). These LBD proteins could be classified into two groups based on the structure of their lateral organ boundaries domain. The promoters of FvLBD genes contain different regulatory elements associated with potential response to different environmental stimuli and plant developmental signals. Furthermore, we analysed the expression patterns of the LBD genes during the callus formation in strawberry and the results suggested that FvLBD16 might play a prominent role in the regulation of callus formation. In addition, we investigated the expression profiles of FvLBD genes during early fruit development based on transcriptome data. We found that some FvLBD genes show a specific expression pattern. These results indicate that FvLBD genes may have a function in early fruit development. Together, the present study provides insights into possible functions of FvLBD genes and provides a basis for further functional research of FvLBD proteins.