Cotton Aquaporin Genes and Their Expression.

Aquaporins are membrane water channel proteins that facilitate inter- and intra-cellular water transport. They are found in all forms of living organisms. In plants, they are present as a multi-gene family in the genome. From previous studies, it has been suggested that aquaporins play a significant role in growth and development. They also appear important in cotton fiber elongation processes. Using the recent outcome from whole genome sequences of cotton genomes, subchromosomal localization of multigene aquaporin members has been characterized. In this study, an expression analysis was performed on highly homologous aquaporins (mostly PIPs and TIPs) that constituted a group of tandem clusters both in two subchromosomal genomes, A and D. It is discussed how these tandem arrayed aquaporin genes are expressed in different tissue types including fibers and whether these conserved aquaporins in tandem repeats act similar each other in subgenomic levels.