EXPRESSION PROFILING OF THE COTTON FIBER TRANSCRIPTOME USING OLIGONUCLEOTIDE MICROARRAYS REVEALS MOLECULAR SWITCHES TO DEVELOPMENTAL PROGRAMS

¹ Department of Agronomy & Range Science, University of California, One Shields Ave., Davis, CA 95616, CA, USA

The development of cotton fibers in discrete stages provides a unique opportunity to study fundamental processes in plant biology in a single cell and in response to developmental and environmental cues. We have a long-standing interest in the genetic mechanism that regulates the rate and duration of fiber expansion, and in turn, how regulation of fiber growth and development dictates the size and shape of the fiber to impart the fiber with its unique agronomic properties. The cotton fiber transcriptome represents a major portion of the cotton genome and is therefore of very high genetic complexity. The highly exaggerated growth of rapidly elongating fibers is reflected in the functional composition of the transcriptome, which indicates a very metabolically active cell type. Expression profiling of cotton long oligonucleotide arrays representing the fiber transcriptome provides a global view of the thousands of expansion-associated genes that are differentially regulated during fiber development. The model of fiber development provides a framework for comparative studies in which perturbation of developmental processes unveils key information about developmental switches and regulatory circuitry that govern fiber development.