Genome-wide analysis of gene expression profiles during the kernel development of maize (Zea mays L.).

Maize kernel is an important source of food, feed, and industrial raw materials. The elucidation of the molecular mechanisms of maize kernel development will be helpful for the manipulation of maize improvements. A microarray with approximately 58,000 probes was used to study dynamic gene expression during kernel development from fertilization to physiological maturity. By comparing six consecutive time points, 3445 differentially expressed genes were identified. These genes were then grouped into 10 clusters showing specific expression patterns using a K-means clustering algorithm. An investigation of function and expression patterns of genes elucidate the regulation mechanism underlying the important developmental processes cell division and kernel filling. The differential expression of genes involved in plant hormone signaling pathways suggested that phytohormone might play a critical role in the kernel developmental process. Moreover, regulation of some transcription factors and protein kinases might be involved in the whole developmental process.