Genome-Wide Identification of Gene Family in and Functional Characterization of , Preferentially Expressed in Phloem.

Thaumatin-like proteins (TLPs) in plants are involved in diverse biotic and abiotic stresses, including antifungal activity, low temperature, drought, and high salinity. However, the roles of the genes are rarely reported in early flowering. Here, the gene family was identified in . The 49 genes were classified into 10 clusters, and gene structures, conserved motifs, and expression patterns were analyzed in these genes. Among 49 genes, the transcription level is preferentially high in stems, and GUS staining signals were mainly detected in the phloem tissues of the pro::GUS transgenic poplars. We generated transgenic plants overexpressing the gene, and its overexpression lines showed early flowering phenotypes. However, the expression levels of main flowering regulating genes were not significantly altered in these -overexpressing plants. Our data further showed that overexpression of the gene led to a reactive oxygen species (ROS) burst in , which might advance the development process of transgenic plants. In addition, subcellular localization of -fused green fluorescent protein (GFP) was in peroxisome, as suggested by tobacco leaf transient transformation. Overall, this work provides a comprehensive analysis of the gene family in and an insight into the role of TLPs in woody plants.