Identification and Functional Analysis of Senescence-Associated Genes in Wheat

Senescence is the final stage of leaf development. During this process, different macromolecules undergo degradation, and the resulting components are transported to developing and storage tissues of the plant. Senescence-associated genes (SAGs) play important roles in this process. Identification and characterization of SAGs are the first steps to interpret the function of these genes and to elucidate the mechanisms of leaf senescence. One of the most effective ways to identify SAGs is to screen for candidate genes using massive genome-scale transcriptomic data such as microarray, RNA-seq, digital RNA expression level data, etc. The basic functional analysis of candidate genes is to observe the phenotypes of transgenic plants, in which the candidate SAGs are overexpressed, knocked down, or knocked out. In this chapter, we outline methods for identifying and characterizing SAGs by microarray analysis in wheat. Methods of gene functional analyses by screening transgenic plants are also described. The protocols described in this chapter could also be used in other plant species, especially for Poaceae plants.