| Abstract Detail
Organelle Biology Alabady, Magdy [1], Wilkins, Thea [2]. Expression profiling of the cotton fiber transcriptome reveals preferential linkage of ubiquitin-proteasome genes to fiber QTL in Pima cotton (Gossypium barbadense L.). Global cotton production involves two genotypes; high-yielding Upland cotton, which accounts for the vast majority of acreage, and Pima or Egyptian cotton valued for its fiber quality (length, strength, fineness, elongation). It is therefore not entirely surprising to discover a bias for Pima alleles to be associated with major QTL for fiber quality, especially QTLs for fiber fineness, strength, elongation and maturity in inter-specific mapping populations. Nonetheless, molecular breeding efforts and molecular dissection of fiber QTL are handicapped by the fact that less than 5% of the fiber transcriptome has been genetically mapped. To gain novel insight into the molecular mechanisms underlying fiber quality in Pima cotton, and to identify fiber QTL candidate genes, expression profiling of the Pima fiber transcriptome was performed as a function of development. One of the metabolic pathways over-represented during Pima fiber development of particular note was the Ubiquitin/26S proteasome proteolytic pathway, which was associated with the highest number of significantly expressed genes. A subset of these Ubiquitin pathway genes mapped to fiber QTLs associated with secondary cell wall-dependent traits such as strength, fineness and elongation. Interestingly, most of these candidate QTL genes belonged to the E3 ligase family based on domain analysis. These findings suggest a significant correlation between secondary cell wall synthesis in developing cotton fibers and the ubiquitin/26S proteasome proteolytic pathway. Further investigation is underway to explore the significance of this relationship from a functional standpoint, which may in turn, lead to the discovery of QTL-genes that play a major role in controlling secondary cell wall synthesis in Pima fiber cells. Log in to add this item to your schedule
1 - Texas Tech University, Plant and Soil Science, Experimental Science Bldg, MS 3213, Lubbock, TX, 79409, USA 2 - Texas Tech Univesity, Plant and Soil Science
Keywords: Functional genomics Cotton fiber cell wall E3 ubiquitin ligase Fiber QTL microarray transcriptome Pima.
Presentation Type: Plant Biology Abstract Session: P Location: Exhibit Hall (Northeast, Southwest & Southeast)/Hilton Date: Sunday, July 8th, 2007 Time: 8:00 AM Number: P18030 Abstract ID:1929 |