MicroRNA-Dependent Gene Regulatory Network for Leaf Senescence in Maize

Maize grain yield depends mainly on the photosynthetic efficiency of functional leaves, which is controlled by an array of gene networks and other factors. MicroRNAs (miRNAs) are small RNA molecules that play important roles in plant developmental regulation. A few senescence-associated miRNAs (SA-miRNAs) have been identified to be regulating leaf senescence by modulating the expression levels of their target genes.

The team of Xiangyuan Wu from Henan Agricultural University in China studied the miRNA roles in leaf senescence and their underlying mechanisms in maize. A stay-green line, Yu87-1, and an early leaf senescence line, Early leaf senescence-1 (ELS-1), were used to determine candidate miRNAs.

Sixteen miRNAs were found to be differentially expressed between ELS-1 and Yu87-1. Analysis of both lines identified these 16 differentially expressed miRNAs as candidate SA-miRNAs. Further analysis indicate that these candidate SA-miRNAs may regulate leaf senescence through their target genes, mainly transcription factors, and potentially control chlorophyll degradation pathways.

For more information on the study, read the full article on BMC Plant Biology.