Expression Profiling and MicroRNA Regulatory Networks of Homeobox Family Genes in Sugarcane L.

Homeobox (HB) genes play important roles in plant growth and development processes, particularly in the formation of lateral organs. Thus, they could influence leaf morphogenesis and biomass formation in plants. However, little is known about in sugarcane, a crucial sugar crop, due to its complex genetic background. Here, 302 allelic sequences for 104 were identified and divided into 13 subfamilies in sugarcane . Comparative genomics revealed that whole-genome duplication (WGD)/segmental duplication significantly promoted the expansion of the HB family in , with , , , , , , and being retained from the evolutionary event before the divergence of dicots and monocots. Based on the analysis of transcriptome and degradome data, we speculated that and might play important roles in regulating sugarcane leaf morphogenesis, with miR166 and SsAGO10 being involved in the regulation of expression. Moreover, subcellular localization and transcriptional activity detection assays demonstrated that these two genes, and were functional transcription factors. This study demonstrated the evolutionary relationship and potential functions of genes and will enable the further investigation of the functional characterization and the regulatory mechanisms of .