Molecular Evolution of PPHLN1 Gene in Relation to HERV-M Element Jae-Won Huh1, Dae-Soo Kim2, Hong-Seok Ha1, Kung Ahn1, Yun-Ji Kim1, Ja-Rang Lee1, and Heui-Soo Kim1,2,* 1 Division of Biological Sciences, College of Natural Sciences, Pusan National University, Busan 609-735, Republic of Korea 2 PBBRC, Interdisciplinary Research Program of Bioinformatics, College of Natural Sciences, Pusan National University, Busan 609-735, Republic of Korea http://www.primate.or.kr MOLECULAR BIOLOGY & PHYLOGENY LAB Abstract Materials & Methods 2 Results & Discussion Novel Alternative Splicing of HERV-M related to PPHLN1 gene HERV-M (the human endogenous retrovirus M), related to the super family of HERV-K, has a methionine (M) tRNA primer-binding site and is located within the periphilin gene on human chromosome 12q12. HERV-M has been integrated into the periphilin gene as the truncated form, 5’LTR-gag-pol-3’LTR. PCR (polymerase chain reaction) and RT-PCR (reverse transcription-polymerase chain reaction) approaches were conducted to investigate its evolutionary origins. Interestingly, the insertion of various retroelements in a common ancestor genome may make different transcript variants in different species. In the case of the periphiline gene, human (10 variants) and mouse (2 variants) lineages show different transcript variants. Insertion of HERV-M (variant 1-3) could affect the protein coding region. Also Alusq/x (variant 4-9) and L1ME4a (mammalian-wide subfamilies of LINE-1) (variant10) in humans and SINE (short interspersed repetitive element) and RLTR15 (the mouse putative long terminal repeat) (variant 2) in mice could be driving forces in transcript diversification of the periphilin gene during mammalian evolution. The HERV-M derived transcripts (variant 1-3) were expressed in various human tissues, whereas it was not detected in crab-eating monkey and squirrel monkey tissues by RT-PCR amplification. Taken together, HERV-M seems to have been integrated into our common ancestor genome after the divergence of simians and prosimians, and then was actively expressed during hominoid evolution...…………………………………………………………………………………… Whole Genome sequence (Golden Path, hg16) Reference Sequence (Feb. 27 2004) dbEST clustering with template (Apr. 01 2004) Human Tissues Cancer cell lines 3 RepeatMasker Adult Stem cells The Structure of PPHLN1 Transcript variants Monkey Tissue Identification of retroelement related Gene Total RNA isolation mRNA subtraction Unidentified Gene Confirm with RT-PCR New finding of Hybrid Genes with HERVs 4 Introduction 1 Results & Discussion Evolution of HERV-M related alternative transcript Insertion of Retroelements during the Evolution of PPHLN1 gene 5 Expression profiling of HERV-M related alternative transcripts Genome Information Laboratory, Pusan National University, Republic of Korea