title: Identification and differential expression patterns of porcine OCT4 variants.
abstract: OCT4 encoded by POU5F1 has a crucial role of maintaining pluripotency in embryonic stem cells during early embryonic development and several OCT4 variants have been identified in mouse and human studies. The objective of this study was to identify different variants of OCT4 and analyze their expression patterns in preimplantation porcine embryos and various tissues. In this study, we showed that POU5F1 transcribes its three variants, namely OCT4A, OCT4B, and OCT4B1. The OCT4B transcript consists of exons identical to the major form of the OCT4 variant, OCT4A, with a differential N-terminal domain-coding exon. The structure of OCT4B1 mRNA was the same as that of OCT4B mRNA, but harbored a cryptic exon. Based on these findings, the transcription levels were investigated and found that OCT4B and OCT4B1 made up ∼20% among the variants in the embryonic stage and this indicates that OCT4A mRNA is dominantly expressed during preimplantation embryo development. In addition, OCT4B mRNA was detected in all tissues examined, while OCT4A and OCT4B1 were detected only in testis but not in other tissues examined. OCT4B1 showed inversely correlated expression with SOX2 and NANOG expression. OCT4A protein was specifically localized to the nuclei, whereas OCT4B was mainly localized to the cytoplasm of the porcine embryos at the blastocyst stage. The findings of this study reveal that the porcine OCT4 gene can potentially encode three variants (OCT4A, OCT4B, and OCT4B1), and they are differentially expressed and would have roles dissimilar between each other in preimplantation embryos and various adult tissues.
authors.affiliation: Department of Agricultural BiotechnologyAnimal Biotechnology Major, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921, KoreaInstitute of Green Bio Science and TechnologySeoul National University, Kangwon-do 232-916, Korea.
authors.forename: Jae Yeon
authors.initials: JY
authors.lastname: Hwang
authors.affiliation: Department of Agricultural BiotechnologyAnimal Biotechnology Major, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921, KoreaInstitute of Green Bio Science and TechnologySeoul National University, Kangwon-do 232-916, Korea.
authors.forename: Jong-Nam
authors.initials: JN
authors.lastname: Oh
authors.affiliation: Department of Agricultural BiotechnologyAnimal Biotechnology Major, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921, KoreaInstitute of Green Bio Science and TechnologySeoul National University, Kangwon-do 232-916, Korea.
authors.forename: Dong-Kyung
authors.initials: DK
authors.lastname: Lee
authors.affiliation: Department of Agricultural BiotechnologyAnimal Biotechnology Major, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921, KoreaInstitute of Green Bio Science and TechnologySeoul National University, Kangwon-do 232-916, Korea.
authors.forename: Kwang-Hwan
authors.initials: KH
authors.lastname: Choi
authors.affiliation: Department of Agricultural BiotechnologyAnimal Biotechnology Major, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921, KoreaInstitute of Green Bio Science and TechnologySeoul National University, Kangwon-do 232-916, Korea.
authors.forename: Chi-Hun
authors.initials: CH
authors.lastname: Park
authors.affiliation: Department of Agricultural BiotechnologyAnimal Biotechnology Major, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921, KoreaInstitute of Green Bio Science and TechnologySeoul National University, Kangwon-do 232-916, Korea Department of Agricultural BiotechnologyAnimal Biotechnology Major, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921, KoreaInstitute of Green Bio Science and TechnologySeoul National University, Kangwon-do 232-916, Korea leeck@snu.ac.kr.
authors.forename: Chang-Kyu
authors.initials: CK
authors.lastname: Lee
mesh_terms: D017398:Alternative Splicing; D000818:Animals; D001483:Base Sequence; D001755:Blastocyst / Q000166:cytology / Q000378:metabolism*; D015153:Blotting, Western; D002454:Cell Differentiation; D004622:Embryo, Mammalian / Q000166:cytology / Q000378:metabolism*; D053595:Embryonic Stem Cells / Q000166:cytology / Q000378:metabolism; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D050810:Octamer Transcription Factors / Q000235:genetics* / Q000378:metabolism*; D020033:Protein Isoforms; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012689:Sequence Homology, Nucleic Acid; D013552:Swine; D014018:Tissue Distribution
chemical_list: D050810:Octamer Transcription Factors; D020033:Protein Isoforms; D012333:RNA, Messenger