Bioinformatics analysis for heat shock protein 90 in flue cured tobacco variety Bright Yellow 2

ObjectiveBioinformatic analysis for heat shock protein 90(HSP90)of tobacco(Bright Yellow 2)was conducted to provide theoretical basis for revealing characteristics of tobacco leaf curing.MethodThe sequences of NtHSP-1,NtHSP-2 and NtHSP-3(respective GenBank accession number:BAL42333,BAL42332 and BAM24708), Bright Yellow 2 HSP90 protein members,were collected from NCBI. The physical and chemical properties,transmem-brane region,signal peptide,subcellular localization,secondary structure and tertiary structure prediction were analyzed by using bioinformatics software.ResultAmino acid numbers of NtHSP-1,NtHSP-2 and NtHSP-3 were 812,811 and 699 respectively. The content of acidic amino acid was the majority,with glutamic acid(Glu)accounting for the highest content. Theoretical isoelectric points of them were all less than 5.00,and the secondary structures were mainlyα-helix (H)and irregular curl(C). NtHSP-1 and NtHSP-2 presented high hydrophilicity and stability. They belonged to secretory protein with anchor structure,and located in endoplasmic reticulum. Their tertiary structures were in"r"shape,having a Mg2+binding site,HATPase_c(ATPase)and top6b(DNA topoisomerase VI)functional domain inside N-end. NtHSP-3 was a non-secreted protein which located in chloroplast. Its tertiary structure was in"i"shape,containing a Mg2+binding site and HATPase_c functional domain at N-end.ConclusionNtHSP-1 and NtHSP-2 may be related to endurable curing potential of tobacco leaves during curing. NtHSP-3 may be related to easy curing potential of tobacco leaves during curing process.