Ectopic expression of BoYAB1, a member of YABBY gene family in Bambusa oldhamii, causes leaf curling and late flowering in Arabidopsis thaliana

The YABBY gene family plays a vital role in the polarity development of lateral organs. Here, we isolated a BoYABBY1 (BoYAB1) gene from Bambusa oldhamii and encodes for 167aa protein. This gene contains a zinc-finger motif in its N terminus and a YABBY domain in its C terminus. Based on multiple sequence alignment, BoYAB1 was shown closely related to OsYAB1 from rice with a sequence identity of 88.76%. Expression analysis (RT-qPCR) and in-situ hybridisation results revealed that the preferential accumulation of BoYAB1 was in the stamen and carpel primordia of flower buds. Ectopic expression of BoYAB1 in Arabidopsis thaliana caused late flowering, narrow while curled leaves, and the curl was pointed towards the abaxial side. Further assays indicated that the observed phenotypic differences were associated with the expression level of exogenous BoYAB1 gene in transgenic plants. These results suggested that the BoYAB1 gene might be involved in leaf development and regulation of flowering time.