Abstract The SFTPB (surfactant, pulmonary-associated protein B) gene on human chromosome 2p11.2 encodes an amphipathic surfactant protein essential for lung function and homeostasis after birth. The SFTPB gene has been investigated to have transcript variants related with transposable elements (LTR7B and AluSx). We investigated the evolutionary aspect and molecular characterization of SFTPB gene using genomic DNAs and RNAs from various primate samples. LTR7B and AluSx elements within the SFTPB gene have been integrated into ancestor genome before the divergence of simian and prosimian. Alu recombination-mediated deletion (ARMD) event has been occurred after the divergence of New World monkeys and Old World monkeys in SFTPB gene 3’ UTR region. Transcript variants (306 bp and 463 bp) were newly identified by comparative RT-PCR analysis. Original transcript (419 bp) shows ubiquitous expression in various tissues and TE fusion transcript (841 bp) shows the lung specific expression in human. Taken together, integration event of LTR7B and AluSx on SFTPB gene seem to cause a lineage specific exonization event via general exonization event (New World monkeys and prosimian), ARMD event (Old World monkeys and hominoids), and alternative splicing (human) during the primate evolution. Ja-Rang Lee 1, Jae-Won Huh 1,2, Dae-Soo Kim 3, Hong-Seok Ha 1, Kung Ahn 1, Yun-Ji Kim 1, Kyu-Tae Chang 2, and Heui-Soo Kim 1,* 1 Division of Biological Sciences, College of Natural Sciences, Pusan National University, Busan , Korea 2 National Primate Research Center (NPRC), KRIBB, Ochang, Chungbuk , Republic of Korea 3 Korea Bioinformation Center, KRIBB, Daejeon , Korea 1. Han, K., Lee J., Meyer, T. J., Wang, J., Sen, S. K., Srikanta, D., Liang, P. & Batzer, M. A. (2007). Alu recombination-mediated structural deletions in the chimpanzee genome. PLoS Genet. 3, Clark JC, Wert SE, Bachurski CJ, Stahlman MT, Stripp BR, Weaver TE, Whitsett JA Targeted disruption of the surfactant protein B gene disrupts surfactant homeostasis, causing respiratory failure in newborn mice. Proc. Natl. Acad. Sci. USA. 92: References Materials & Methods Bioinformatics Genomic DNA & cDNA RT-PCR Human, Rhesus monkey & Marmoset(30 cycle) ; Various tissues PCR & Cloning of PCR product 30 cycle; 94 ℃ - 40 sec, 56 ℃ - 30 sec, 72 ℃ - 40 sec Qiaquick Gel-extraction, Promega T-easy Vector, EcoR-I(DH5α) Genomic DNA of various primate and human cDNA of various tissues of human, rhesus monkey & marmoset Introduction Other region 16% Gene-related Sequence 36% LINE 20% SINE 13% Coding sequence 3% Pseudogene 1% HERV element 8% DNA element 3% Results & Discussion Chr _A 10 NM_ bp S1 AS NM_ _B 2p11.2 SFTPB Gene Structure 638 bp S1 AS2 SFTPB Gene Expression in Various Tissues of Human 841 bp 306 bp G3PDH 120 bp Adrenal glandBone marrow Cerebellum Whole brain Fetal brainFetal liver HeartKidneyMarkerLiverLung Placenta Marker Testis Thymus Prostate Salivary gland Thyroid UterusTrachea Skeletal muscleSpinal cord Adrenal glandBone marrow Cerebellum Whole brain Fetal brainFetal liver Heart Kidney Marker Liver Lung Placenta Marker Testis Thymus ProstateSalivary gland Thyroid Uterus Trachea Skeletal muscle Spinal cord 419 bp G3PDH 120 bp 841 bp SAS NM_ New Transcript NM_ New Transcript 419 bp SAS 463 bp Cerebellum Cerebrum Stomach Pancreas Adrenal gland Heart Kidney LiverLungTestis Marker Trachea Spleen CecumMarker Rectum Urine bladder GulletDuodenum Tongue Jejunum Salivary gland ColonIleum 306 bp G3PDH 120 bp Adrenal glandCerebellum CerebrumHeart Kidney Liver LungTestis Marker Trachea Spleen CecumMarker Rectum Urine bladder GulletStomachDuodenum TongueJejunum Pancreas Salivary gland Colon Ileum G3PDH 120 bp 463 bp SFTPB Gene Expression in Various Tissues of Rhesus monkey 419 bp SFTPB Gene Expression in Various Tissues of New World monkeys Marker BrainHeart Kidney Liver LungMarker Cerebellum Heart Kidney Lung Uterus 306 bp G3PDH 120 bp 306 bp G3PDH 120 bp Marker Cerebellum Heart Kidney Liver Lung Cerebellum HeartKidney Lung Uterus Marker G3PDH 120 bp 463 bp 419 bp G3PDH 120 bp 638 bp HU CH GO OR GI JM RH NM Marker TA RL 392 bp HU CH GO OR GI JM RH NM Marker TA RL 763 bp ARMD event and evolutionary aspect of the SFTPB gene Integration lineage of HERV-H LTR and AluSx in the SFTPB gene ARMD event AluSg vs AluSxAluSxAluJLTR7B ? AluSgAluSxAluJLTR7B Insertion of TEs ARMD event Alternative splicing