Identification, sequencing and characterization of a stress induced homologue of fructose bisphosphate aldolase from cotton

A drought-induced homologue of fructose-1, 6 bisphosphate aldolase full length cDNA (GaAldp) was isolated and sequenced by gene homology and rapid amplification of cDNA ends (RACE) from cotton variety FDH-786 (Gossypium arboretum). Quantitative polymerase chain reaction (PCR) analysis showed that drought stress, salinity and exogenous treatment with abscisic acid (ABA) enhanced the accumulation of GaAldp transcripts in the leaf and stem tissues of the plant. An alignment of the 1413 bp cDNA and 1937 bp genomic DNA sequences revealed that GaAldp has an open reading frame (ORF) encoding 394 amino acids and contains five introns. The predicted amino acid sequence is homologous to a heat-induced isoform of oat chlorplastic fructose bisphosphate aldolase (FBP) (AF216582) and NPALDP1 from Nicotiana paniculata. The GaAldp sequence includes a novel stroma targeting N-terminal transit peptide (TP) of 45 amino acids, which is 63-76% similar to other chloroplastic TPs.Key words: Fructose-1, 6 bisphosphate aldolase, Gossypium arboreum, drought, abscisic acid, transit peptide, salt stress