Comparison of antigenic sites of the envelope glycoprotein of the Iranian isolate of human T-cell leukemia virus type 1 with different subtypes of the virus

Human T-cell leukemia virus type 1 [HTLV-1] is an enveloped retrovirus, which is associated with a T-cell malignancy known as adult T-cell leukemia [ATL]. Variation in the HTLV-1 envelope nucleotide sequence has been extensively documented and has been used to classify HTLV-1 isolates into different subtypes. The virus occurs in at least 3 subtypes, which have been named A, B, and C. We conducted this study to compare the antigenic proprieties of the Iranian isolate of HTLV-1 with the homologous region of different subtypes of the virus. This study took place in the Department of Biology, College of Sciences, Shiraz University, Iran in 2005. The predicted antigenic sites and secondary structure of the envelope glycoprotein of HTLV-1, present in Iran, have been compared with the antigenic sites and secondary structure of the homologous domains in subtypes A, B, C of the virus. To predict the epitopes of glycoproteins, 21 different scales were used. The number of helices in the Iranian isolate was equal to the number of these regions in all 3 subtypes, but the number of beta-sheets was more than other viruses. One potential glycosylation site, on all these studied envelope glycoproteins, was predicted. Antigenic sites in the Iranian isolate were almost similar to subtype A of the virus and the Iranian isolate of HTLV-1 may be belongs to subtype A. Our results indicate the similarities and differences between the Iranian and other subtypes of HTLV-1. Antigenic sites represent potential candidates for use in a peptide vaccine against HTLV-1 glycoproteins and since most of the properties of a particular protein depend on its structural properties, this type of study can help in better understanding of HTLV-1 isolates present in Iran

Identification of human chromosome segments that have high homology with rat genomic DNA

This study was conducted to determine the location of DNA segment with homology to the rat conserved genomic DNA in human chromosomes. The labeled rat genomic DNA was hybridized with normal human [male] metaphases. The study of 74 metaphases after fluorescence in situ hybridization showed 371 twin-spot signals on human chromosomes. Statistical analysis indicated that the specific accumulation of signals on lq22-qter, 2p2, 3p21-p23, 4q3, 6q2, 8pl2-pter, llpl2-pter, llql2-qter, 12q2, 13p, 15p, 16q2, 21ql2-qter, Yql-qter, and Xq2 was not r and om. Results of stepwise multiple linear regressions indicated that number of mapped oncogenes [Beta = 1.092; t = 7.552; P<0.001] and density of mapped oncogenes on chromosomes [Beta = -0.832; t = -5.751; P<0.001] have significant effects on number of double-spots on human chromosomes. These data reflects the evolutionary conservation between rat DNA and human DNA at the above-mentioned b and s