Evolutionary diversification of DYX1C1 gene Evolutionary diversification of DYX1C1 gene transcripts by HERV-H LTR integration event transcripts by HERV-H LTR integration event Results & Discussion Abstract DYX1C1 (dyslexia susceptibility 1 candidate 1) gene on human chromosome 15q21.3 is a candidate gene for de velopmental dyslexia. The DYX1C1 shows three alternati vely spliced transcripts in GenBank database. We found that one of transcripts is related to HERV-H LTR eleme nt that could affect the protein-coding region. The HE RV-H LTR element on human DYX1C1 gene seems to have be en integrated into our common ancestor genome after th e divergence of Old World monkeys and New World monkey s. RT-PCR analysis of HERV-H LTR-related transcript sh ows that five different alternative transcripts are ex pressed in several human tissues. Five different alter native splicing forms are also identified in various r hesus monkey tissues. From the sequencing analysis of various primate DNA samples, we found the lineage spec ific tandem repeated sequences of Old World monkeys in protein coding region. However, the formation of tande m repeated sequences did not affect the amino acid seq uences. Taken together, integration event of the HERV- H LTR element contributed to the DYX1C1 gene diversifi cation by affecting protein coding region during the p rimate evolution.………………………………………………………………………..… Yun-Ji Kim 1 , Jae-Won Huh 1 , Dae-Soo Kim 2 , Hong-Seok Ha 1 , Kung Ahn 1 , Ja-Rang Lee 1 , Min-In Bae 1 , and Heui-Soo Kim 1, 2 1 Division of Biological Sciences, College of Natural Sciences, Pusan National University, Busan 609-735, Republic of K orea 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 Materials & Methods Plasmid DNA Isolation Transformation-Inoculation Ligation Electrophoresis-Gel purification Polymerase Chain Reaction (PCR) Gene Cloning Genomic DNAs & cDNA PCR & RT-PCR Bioinformatics QIAEX II gel extraction kit(Qia gen) High Pure plasmid isolation kit Human Monkey NCBI,BLAST,MEGA3 Introduction Chr.15 q21.3 NM_001033560.1 10 EXON1 2 3 4 5 6 7 8 9 EXON1 2 3 4 5 6 7 8 9 EXON1 2 3 4 5 6 7 8 9 NM_001033559.1 NM_13081.2 EXON1 2 3 4 5 6 7 8 9 EXON1 2 3 4 5 6 7 8 9 EXON1 2 3 4 5 6 7 9 NEW TRANSCRIPTS EXON1 2 3 4 5 6 7 9 V1 V1-1 V2 V3 V1-2 V1-3 V1-4 7’ 8’ 8’ S AS S AS M HU CH GO OR GI JM RH NM SQ CM 799 bp 1.Sin HS, Huh JW, Kim DS, Kang DW, Min DS, Kim TH, Ha HS, Kim HH, Lee SY, Kim HS. (2006) Transcriptional control of the HERV-H LTR element of the G SDML gene in human tissues and cancer cells. Arch Virol. 151(10):1985-94. 2. Okahara G, Matsubara S, Oda T, Sugimoto J, Jinno Y, Kanaya F. (2004) Expression analyses of human endogenous retroviruses (HERVs): tissue-specif ic and developmental stage-dependent expression of HERVs. Genomics. 84(6):982-90 References V1 V1-3 V1-4 V1- 1,V1-2 GAPDH 120 bp GAPDH 120 bp V3 V2 Number 1 2 3 4 5 6 7 8 Tissues adrenal gland cerebellum heart kidney liver lung testis trachea Human Intergation Time LTR in CDS 0.01 71 96 42 10 0 56 DYX1C1 HU DYX1C1 CH DYX1C1 GO DYX1C1 GI 10 0 DYX1C1 JM DYX1C1 RH DYX1C1 CM DYX1C1 SQ DYX1C1 NM LTR7 M 1 2 3 4 5 6 7 8 M 1 2 3 4 5 6 7 8 GAPDH 120 bp V1 V1-3 V1-4 V1- 1,V1-2 GAPDH 120 bp V3 V2 Model for DYX1C1 gene evolution Rhesus Coding region Untranslated regi on LTR7 M 1 2 3 4 5 6 7 8 M 1 2 3 4 5 6 7 8 Retroelement Retroposon SINE Retrotransposon LINE RNA intermediate - LTR element + LTR element - env + env - RT + RT Yeast Ty1/copia/truncated HERVs LTR ORF1 ORF2 LTR LTR LTR Human THE1 P Poly(A) Human Alu ORF1 ORF2 P Poly(A) L1 Retrovirus gag pol env LTR LTR Full-length HERVs/exogenous retrovirus Human Common ancesto r Rodent s ancest or Primat e ancest or Mous e Ra t New World monkey Old World monkey LTR 7 PB1D9 B1F Tandem duplication