HERVs (Human endogenous retroviruses) and LTR (long terminal repeat) - like elements are disperse d over 8% of the whole human genome. There are at least 22 independent HERV families within the h uman genome, which originated from germ-cell infection by the exogenous retrovirus during primate evolution. Elucidation of expression pattern in HERV elements should provide information about fu ndamental cellular activities and the pathogenesis of multifactorial diseases such as cancer and autoimmune disease. HERV-W env gene is related to multiple sclerosis, and has potential roles for normal differentiation of human villous cytotrophoblast into syncytiotrophoblast. HERV-W env gene was expressed differentially in human tissues. Especially, it was highly expressed in human place nta. This phenomenon indicates HERV-W env gene have the different roles in each tissues. Here, we applied realtime RT-PCR for detection of its expression in various human tissues. We also analyse d such amplification using cancer cells and monkey tissues, and discussed in relation to physiolo gical function. ____________________ Retroelement Retroposon SINE Retrotransposon Retrovirus LINE RNA intermediate - LTR element + LTR element - env + env - RT + RT gag pol env LTR LTR Human Alu ORF1 ORF2 P Poly(A) L1 Full-length HERVs/exogenous retrovirus P LTR LTR LTR LTR ORF2 ORF1 Poly(A) Yeast Ty1/copia/truncated HERVs Human THE1 Pseudogenes LTR LTR provirus LTR LTR Enodgenous retrovirus Exogenous Retro viruses Retrotranspos ons Endogenous Re troviruses buddin g proteins (gag, en v) translat ion infectio n REVERSE TRANSCRIPTION transcrip tion integrat ion cDNA AAA mRNA AAA mRNA transcrip tion LTR LTR re - integrat ion translation proteins (gag, en v) REVERSE TRANSCRIPTION cDNA Particle formation(buddi ng) LTR LTR re - integrat ion Particle formation no re-infec tion LTR LTR retrotranspo son AAA transcrip tion mRNA cDNA REVERSE TRANSCRIPTION Cellular g ene pseudoge ne splicing AAA REVERSE TRANSCRIPTION cDNA integrat ion transcrip tion spliced- mRN A translation proteins (gag) Other region 16% Gene-related Sequence 36% LINE 20% SINE 13% Coding sequence 3% Pseudogene 1% HERV element 8% DNA element 3% Primer Design Twenty Di fferent Human tis sue cDNAs Quantitative Analysis Realtime RT-PCR using SYBR Green I Extension(II) phase Extension(I) phase End of PCR cycle Annealing phase SYBR Green I Detection of fluorescence Experimental Procedure relative quantification normalisation via one reference gene via reference gene index >3HKG external calibration curve without any reference gene without real-time PCR efficiency correction 2 (-△△CP) with real-time PCR efficiency correction REST, qGene LC software & etc... 1. Gapdh standard 2. W-env standard 3. Meting graph 5. Tissue melting graph 4. Tissue expression graph 0 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0 0.002 0.004 0.006 0.008 0.01 0.012 0.014 0.016 6. Relative quantitative analysis of w-env expression 7. Relative quantitative analysis of w-env expression except for placenta Yi JM and Kim HM and Kim HS 2004. Expression of the human endogenous retrovirus HERV-W family in various human tissues and cance J. Gen. Virol. 85: 1203-1210. Yi JM, Osamu T and Kim HS 2003. Molecular characterization and phylogenetic relationship of HERV-W family in the Macaca fuscat Arch. Virol. 148(8) 1613-1622. Placent a Adrenal glan d Bone marro w Cerebellu m Brai n Fetal brai n Fetal live r Hear t Kidne y Live r Lun g Prostat e Salivary glan d Skeletal muscl e Spinal cor d Testi s Thymu s Thyroi d Trache a Uteru s Adrenal glan d Bone marro w Cerebellu m Brai n Fetal brai n Fetal live r Hear t Kidne y Live r Lun g Prostat e Salivary glan d Skeletal muscl e Spinal cor d Testi s Thymu s Thyroi d Trache a Uteru s