摘要
Maize(Zea mays),a major crop for food and feed,is grown world-wide with a high annual yield.The grain size and weight of maize are mainly determined by starch and storage proteins that are actively synthesized during endosperm filling.During early endo-sperm development,the maize endosperm undergoes a series of cell division,differentiation,and expansion events.Cell division and expansion determine the number and size of endosperm cells,respectively,influencing the final grain size and yield.While cell division mainly occurs during early endosperm development,cell expansion occurs continuously,particularly during the endo-sperm filling stage when starchy endosperm cells are enlarged with storage metabolites.Despite several key genes involved in the regulation of either endosperm filling or cell expansion being identified,how these two processes are coordinated remains elusive.
