Project description:The present study profiled and analyzed gene expression of the maize ear at four key developmental stages. Based on genome-wide profile analysis, we detected differential mRNA of maize genes. Some of the differentially expressed genes (DEGs) were predicted to be potential candidates of maize ear development. Several well-known genes were found with reported mutants analyses, such as, compact plant2 (ct2), zea AGAMOUS homolog1 (zag1), bearded ear (bde), and silky1 (si1). MicroRNAs such as microRNA156 were predicted to target genes involved in maize ear development. Antisense transcripts were widespread throughout all the four stages, and are suspected to play important roles in maize ear development. Thus, identification and characterization of important genes and regulators at all the four developmental stages will contribute to an improved understanding of the molecular mechanisms responsible for maize ear development. Seeds of the maize inbred line 18-599 (Maize Research Institute, Sichuan Agricultural University, Chengdu, China) were grown in a growth chamber at 24°C/18°C (day/night) with 12 h illumination per day. Ears were collected as described previously [10] at four developmental stages: the growth point elongation, spikelet differentiation, floret primordium differentiation, and the floret organ differentiation phases. In brief, ears were manually collected at the four developmental stages. All the samples were harvested and immediately frozen in liquid nitrogen, and stored at -80°C until used for RNA isolation.