Molecular cloning and characterization of novel heat shock protein 90 gene from a wild <Emphasis Type="Italic">Vitis pseduoreticulata</Emphasis> native to China

Heat shock protein 90 (Hsp90), known as molecular chaperone, is involved in protein folding and assembly in the cell. In the present study, a full-length cDNA named Vitis pseduoreticulta heat shock protein 90 (VpHsp90) (GenBank accession Number:EU239815), encoding a heat shock protein 90, was obtained by degenerated primers and 3′-and 5′-RACE from Vitis pseudoreticulata according to our previously obtained EST sequence (GenBnak accession number:DV182112), putatively known as Hsp90. Comparison of VpHsp90 sequence has revealed that an open reading frame (ORF) consists of 2,100 bp nucleotides and the translated proteins of 699 amino acid residues. The molecular mass of VpHsp90 calculated from the deduced amino acid sequence was 80.2 kDa, Isolectric Point was 4.893, which is in close proximity of Hsp90. The maximum similarity of VpHsp90 at nucleotides level (85%) and protein level (96%) was found to be with Nicotiana tabacum. Phylogenetic tree analysis at both the nucleotides and amino acids levels indicates that Vitis pseduoreticulata, Nicotiana tabacum, and Arabidopsis thaliana Hsp90 sequences comprise one clade, which is closely related to Oryza sativa, Hordeum vulgare and Triticum aestivum Hsp90s. It may be reasonably concluded that VpHsp90 possesses the ancestral gene of Hsp90 similar to that of higher plant species.