ABSTRACT

Cotton, the world's most important natural fiber, is mostly cellulose. More higher strength cottons are needed as yarn and textile manufacturers adopt high speed production machinery. The enzyme responsible for cellulose production is the multi-meric cellulose synthase, of which we know most about the catalytic subunit, CesA. The question is why does the simplest, fiberless, genome, Arabidopsis, contain 13 CesA loci while with fibered cotton only 5 have so far been identified. Genomic DNA was extracted from young leaves of Gossypium hirsutum and G. barbadense and used for PCR using a primer pair targeted towards the 5' region of the CesA gene. Amplified fragments were cloned and sequenced in the reverse and forward directions and the consensus sequences aligned and analyzed using web-based software. Phylograms, including known G. hirsutum and Arabidopsis CesA sequences, revealed that tetraploid cottons have at least one new CesA family member. Also, there were indications that CesA pseudogenes may also exist in both genomes.