Comparative analysis of PLATZ transcription factors in six poplar species and analysis of the role of PtrPLATZ14 in leaf development.

Plant AT-rich sequence and zinc-binding (PLATZ) proteins are a class of plant-specific transcription factor that play a crucial role in plant growth, development, and stress response. However, the evolutionary relationship of the PLATZ gene family across the Populus genus and the biological functions of the PLATZ protein require further investigation. In this study, we identified 133 PLATZ genes from six Populus species belonging to four Populus sections. Synteny analysis of the PLATZ gene family indicated that whole genome duplication events contributed to the expansion of the PLATZ family. Among the nine paralogous pairs, the protein structure of PtrPLATZ14/18 pair exhibited significant differences with others. Through gene expression patterns and co-expression networks, we discovered divergent expression patterns and sub-networks, and found that the members of pair PtrPLATZ14/18 might play different roles in the regulation of macromolecule biosynthesis and modification. Furthermore, we found that PtrPLATZ14 regulates poplar leaf development by affecting cell size control genes PtrGRF/GIF and PtrTCP. In conclusion, our study provides a theoretical foundation for exploring the evolution relationships and functions of the PLATZ gene family within Populus species and provides insights into the function and potential mechanism of PtrPLATZ14 in leaf morphology that were diverse across the Populus genus.