title: Identification of unique thyrotropin receptor (TSHR) splice variants in the chicken: the chicken TSHR gene revisited.
abstract: We previously described the cloning of the full-length chicken thyrotropin receptor (TSHRa) and two splice variants, lacking exon 3 (TSHRb) or both exons 2 and 3 (TSHRc). Here we report the identification of three novel splice variants of the chicken TSHR, named TSHRd, -e and -f, differing in their C-terminal region and containing unique exonic sequences that are not present in the other TSHR variants. This finding suggests a TSHR gene structure with 13 rather than the previously assumed 10 exons. The three novel exons appear to be chicken-specific, as no equivalents of these exons were found in other vertebrate genomes. Like the full-length receptor, the five TSHR splice variants are most abundantly expressed in thyroid gland. TSHRb, -d, -e and -f mRNA was also present in virtually all extra-thyroidal tissues expressing TSHRa, whereas TSHRc shows a more restricted tissue distribution. Whether these receptor transcripts are translated to functional proteins needs to be verified, but if so, they could be attributed various physiological roles.
authors.affiliation: Research group of Comparative Endocrinology, Animal Physiology and Neurobiology Section, Department of Biology, Catholic University of Leuven, Naamsestraat 61, Box 2464, 3000 Leuven, Belgium.
authors.forename: Sylvia V H
authors.initials: SV
authors.lastname: Grommen
authors.forename: Shusuke
authors.initials: S
authors.lastname: Taniuchi
authors.forename: Veerle M
authors.initials: VM
authors.lastname: Darras
authors.forename: Sumio
authors.initials: S
authors.lastname: Takahashi
authors.forename: Sakae
authors.initials: S
authors.lastname: Takeuchi
authors.forename: Bert
authors.initials: B
authors.lastname: De Groef
mesh_terms: D000818:Animals; D002642:Chick Embryo; D002645:Chickens / Q000235:genetics / Q000502:physiology*; D017931:DNA Primers; D005091:Exons / Q000235:genetics; D021141:Nucleic Acid Amplification Techniques; D020033:Protein Isoforms; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D011989:Receptors, Thyrotropin / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014018:Tissue Distribution
chemical_list: D017931:DNA Primers; D020033:Protein Isoforms; D012333:RNA, Messenger; D011989:Receptors, Thyrotropin