Isolation and characterization of stress related Heat shock protein calmodulin bindinggene from cultivated cotton (Gossypium hirsutumL.)

Abstract

Due to the important role of cotton drought tolerant varieties and the reported involvement in this trait of Heat-shock protein calmodulin binding, the respective gene (HSPCB) was isolated and characterized from cultivated cotton, Gossypium hirsutum (Zeta 2 cultivar), using a chromosome-walking technique. Segments of 3079 bp genomic and 1572 bp cDNA sequences were obtained. Alignments revealed that the HSPCB cDNA contains a single open reading frame of 1374 bp comprising the complete coding region and that the gene possesses five exons. The predicted amino acid sequence shares 72, 54, 58, 32, 31, 27, 28 and 27% identities with A. thaliana, rice, tobacco, Penicillium camemberti, Rhizopus oryzae, Thermomyces lanuginosus, Rhizomucor miehei, Aspergillus niger Lipase/HSPCB proteins, respectively. In addition, the expression profile of this gene was preliminary studied in different plant tissues. Reverse transcription-polymerase chain reaction (RT-PCR) was performed using total RNA samples from leaves, stems and roots of the Australian cotton variety Siokra L23, known for its drought tolerance, isolated after a 4-d osmotic stress treatment (i.e. at the end of the stress period). Semi-quantitative transcription analysis indicated that, under the experimental conditions employed in present study, the gene is expressed in all plant tissues examined.

Understanding the molecular events underpinning cultivar differences in the physiological performance and heat tolerance of cotton (Gossypium hirsutum)

“…Although the optimal temperature range of 20-25 C used for A. thaliana (Busch et al 2005;Kant et al 2008;Larkindale and Vierling 2008) is considerably lower compared with an optimal temperature range of 28-32 C for cotton (Gossypium hirsutum L.) (Burke et al 1988), HSPs and heat shock factors are induced after short-term exposure to high temperatures or water deficit stress for both species (Voloudakis et al 2002;Sotirios et al 2006). Studies comparing relative photosynthesis, chlorophyll fluorescence, membrane integrity, enzyme viability and stomatal conductance in cotton cultivars under high temperatures in a growth cabinet or field situation have shown that significant genotypic variation for plant physiological performance, which may contribute to heat resistance (de Ronde and van der Mescht 1997; Pettigrew and Turley 1998;ur Rahman et al 2004;Rahman et al 2005;Bibi et al 2008;Cottee et al 2010).…”