Gene expression in B73 maize aleurone and starchy endosperm at 18 and 22 day after pollination

The cereal endosperm consists of starchy endosperm (ST) cells, which accumulate storage proteins and starch, the peripheral aleurone (AL) cells, which mobilize these storage compounds during germination, and transfer cells in contact with the maternal vascular tissues, and the embryo-surrounding region. We conducted RNA-sequencing and analyzed transcript profiles of AL and ST tissues at 18 and 22 days after pollination (DAP), when storage compounds such as proteins, starch, triacylglycerols, specialized metabolites, and minerals are actively synthesized in the maize endosperm. We combined published RNA-seq datasets from other kernel tissues at different developmental stages to analyze gene expression connected to synthesis and accumulation of storage compounds and metabolites. Using weighted correlation network analysis (WGCNA), we identified gene modules associated with metabolic pathways related to nutritional properties of the maize endosperm. We also provide information of novel marker genes specifically expressed in AL and ST, at either early or late developmental stages. This study is important for understanding maize endosperm development and for developing strategies to improve nutritional quality of maize kernels. Overall design: We examined B73 maize aleurone and starchy endosperm at 18 and 22 day after pollination,respectively. We collected 2 biological replicates for each tissue sample for RNA-sequencing.

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