Conservation and Divergence of PEPC Gene Family in Different Ploidy Bamboos

Phosphoenolpyruvate carboxylase (PEPC), as a necessary enzyme for higher plants to participate in photosynthesis, plays a key role in photosynthetic carbon metabolism and the stress response. However, the molecular biology of the <i>PEPC</i> family of Bambusoideae has been poorly studied, and the function of its members in the growth and development of Bambusoideae is still unclear. Here, we identified a total of 62 PEPC family members in bamboo. All the <i>PEPC</i> genes in the bamboo subfamily were divided into twelve groups, each group typically containing significantly fewer <i>PEPC</i> members in <i>Olyra latifolia</i> than in <i>Phyllostachys edulis</i>, <i>Dendrocalamus latiflorus</i> and <i>Dendrocalamus brandisii</i>. The results of an intraspecific and interspecies collinearity analysis showed that fragment replication and whole genome replication were the main driving forces of bamboo <i>PEPC</i> members. Furthermore, the <i>Ka</i>/<i>Ks</i> values of collinear genes showed that bamboo <i>PEPC</i> experienced purification selection. In addition, the promoter region of <i>PEPC</i> genes contains cis-acting elements related to light response, plant hormone response and response to stress. An analysis of the expression levels of the <i>PEPC</i> family in different developmental stages and tissues of bamboo shoots has shown that <i>PhePEPC7</i>, <i>PhePEPC9</i> and <i>PhePEPC10</i> were highly expressed in the leaves of non-flowering plants and culms. Furthermore, <i>PhePEPC6</i> was significantly upregulated in leaves after GA treatment. Further research has shown that <i>PhePEPC6</i> was mainly localized in the cell membrane. This provides a solid bioinformatics foundation for further understanding the biological functions of the bamboo <i>PEPC</i> family.