ABSTRACT: The cotton (Gossypium arboreum) stress-related gene GHSP26 responds to dehydration. To elucidate its stress tolerant mechanism at the transcriptional level, we isolated and characterized
the promoter region (PGHSP26, −2,831bp) flanking the 5′ GHSP26 coding region from the genomic DNA. A series of PGHSP26 deletion derivatives was created for the identification of the upstream
region of the gene required for the promoter activity. Each deletion construct was analyzed by agrobacterium mediated transient
transformation in tobacco leaves after treatment with abscissic acid (ABA), heavy metals and dehydration. Promoter fragments
of 716bp or longer showed two-fold or greater induction after each treatment. These findings further our understanding of
the regulation of GHSP26 expression and provide a new drought-inducible promoter system in transgenic plants.
Molecular Biology Reports 04/2012; 36(7):1915-1921. · 2.93 Impact Factor
ABSTRACT: Two closely related genes GUSP1 and GUSP2, within the universal stress protein (USP) family, were identified and cloned from water-stressed leaves of Gossypium arboreum. GUSP1 and GUSP2 genes code for proteins with predicted molecular weights of 18.2 and 19.1kDa, respectively. Sequence analysis showed that
GUSP1 and GUSP2 are highly similar to the bacterial MJ0577-type of adenosine-triphosphate-binding Usp proteins, which have been proposed
to function as a molecular switch. Nucleotide sequences of these two genes showed 81% sequence similarity while their encoded
proteins share 75% amino acid homology. Both proteins have high percentages of similarity (17% to 61%) to the USPs from a
variety of bacteria and plants. Real-time polymerase chain reaction expression analysis revealed a high level of GUSP gene
expression in leaves, roots, and stems exclusively in plants following water stress. The highest levels of drought-inducible
expression were found in the leaves. A progressive decrease in expression was observed in the stem and roots compared to very
low expression in control tissues.
Plant Molecular Biology Reporter 04/2012; 27(1):109-114. · 2.45 Impact Factor
ABSTRACT: The 949 bp promoter fragment upstream from the translation initiation site of the GUSP gene encoding a universal stress protein was isolated from the genomic DNA of Gossypium arboreum. Some putative cis-acting elements involved in stress responses including E-box, ABRE, DPBF-box, and MYB-core elements were found in the promoter
region. In an Agrobacterium-mediated transient expression assay, strong activation of the GUSP full promoter region occurred in tobacco leaves following dehydration, abscisic acid, salt, heavy metal, gibberellic acid
and dark treatments. Deletion analysis of the promoter revealed that the dehydration, abscisic acid and salt responses were
affected by the deletion between −208 and −949 bp and showed 2–4-fold induction. However, in response to dark, gibberellic
acid and heavy metals the induction was only 2-fold. These findings further our understanding of the regulation of GUSP expression. This is an important study as no report of this universal stress protein promoter is available in literature.
Molecular Biology 04/2012; 43(4):578-585. · 0.66 Impact Factor
ABSTRACT: Heat-shock proteins (HSP) are molecular chaperones for protein molecules. These proteins play an important role in protein-protein interactions such as, folding and assisting in the establishment of proper protein conformation and prevention of unwanted protein aggregation. A small HSP gene GHSP26 present in Gossypium arboreum responds to dehydration. In the present study, an attempt was made to overcome the problem of drought stress in cotton. A cDNA of GHSP26 was isolated from G. arboreum, cloned in plant expression vector, pCAMBIA-1301 driven by the cauliflower mosaic virus 35S promoter and introduced into Gossypium hirsutum. The integration and expression studies of putative transgenic plants were performed through GUS assay; PCR from genomic DNA, and quantitative real-time PCR analysis. Transgenic cotton plants showed an enhanced drought tolerance, suggesting that GHSP26 may play a role in plant responsiveness to drought.
Biotechnology Progress 10/2009; 26(1):21-5. · 2.34 Impact Factor