Submitted to: Plant and Animal Genome VX Conference Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 12/21/2008
Publication Date: 1/5/2009
Citation: Taliercio, E.W., Scheffler, J.A., Kwanyuen, P. 2009. Differential Gene Expression in Developing Cotton Stems and Roots. Plant and Animal Genome VX Conference Abstracts.
Technical Abstract: Cotton (Gossypium hirsutum L) is a perennial plant that stores starch in stems and roots to provide carbohydrates for growth in subsequent seasons. These reserves may not be available to support seed and fiber development when cotton is grown as an annual crop. Analysis of developing cotton plants indicated that starch levels peaked about the time of first anthesis and then began to decline. An earlier peak in levels of starch was occasionally observed and in some greenhouse-grown samples starch increased until two weeks after first bloom. Microarray analyses compared gene expression in tissues containing low levels of starch with tissues rapidly accumulating starch. Identification of differentially expressed genes indicated increased expression among genes associated with carbohydrate metabolism, transcription activity and the proteasome. Genes associated with starch synthesis, starch degradation, sucrose metabolism, hexose metabolism, raffinose synthesis and trehalose synthesis increased in expression in starch accumulating tissues. The anticipated changes in these sugars were largely confirmed by measuring soluble sugars in relevant tissues. We suggest trehalose played a role in starch accumulation in cotton similar to its role in Arabidopsis. We also reevaluate physiological and genetic data to update our understanding of the role of starch in cotton development.