Submitted to: National Cotton Council Beltwide Cotton Conference
Publication Type: Abstract Only
Publication Acceptance Date: January 15, 2009
Publication Date: March 20, 2009
Citation: Park, W., Bauer, P.J., Campbell, B.T. 2009. The aquaporin gene family of cotton [abstract]. National Cotton Council Beltwide Cotton Conference. Abstract No. 8988. Technical Abstract: Aquaporin proteins are found in most living organisms and are quite diverse in plants where they function as transport systems for water and other small molecules. Plant aquaporins have been shown to be differentially regulated under environmental stress such as drought, salt and cold treatment. The plant aquaporins belong to the large major intrinsic protein (MIP) family and consist of 5 subfamilies including plasma membrane intrinsic proteins (PIP), tonoplast intrinsic proteins (TIP), NOD26-like intrinsic proteins (NIP), small basic intrinsic proteins (SIP), and the recently discovered X intrinsic protein (XIP). Using conserved domain sequences obtained by comparing cotton EST/nucleotide data with sequences from other plants, we designed degenerate PCR primers to identify the complete aquaporin gene family in cotton (Gossypium hirsutum L). From this molecular cloning effort together with homology search, more than 40 cotton aquaporin proteins were identified. These data suggest the cotton aquaporins are as divergent as other plant species. The cotton aquaporins consist of more than 10 members each in the PIP, TIP, and NIP subfamilies while also containing fewer, less divergent members of the SIP and XIP subfamilies. To explore the physiological roles of these aquaporin genes in cotton, expression analysis was performed using semi-quantitative RT-PCR. Our results suggest that many cotton aquaporin transcripts are regulated tissue specifically.