title: Comparative biology and expression of TENP, an egg protein related to the bacterial permeability-increasing family of proteins.
abstract: The 'transiently expressed in neural precursors' (TENP) gene product is a member of the bacterial/permeability-increasing (BPI) family of antimicrobial proteins but was first identified as having a role in an early neurological event occurring in post-mitotic cells. However, recent characterisation of the egg white proteome has shown that TENP is an important egg component constituting ~0.1-0.5% of the total protein and suggesting it is expressed in the adult oviduct. In this study we confirmed quantitatively that the expression of TENP is largely confined to the tubular glands of the magnum of the oviduct, where egg white synthesis occurs, with around 10,000 times more expression than in the embryo where TENP was first identified. TENP expression is significantly increased with the administration of oestrogen or progesterone (P<0.001) and is reduced in regressed oviducts (P<0.001) demonstrating gonadal steroid control, typical of an oviduct and egg specific gene. A putative translational start site for TENP has been characterised and the evidence indicates that it is expressed as one predominant transcript. In comparison with the published sequence, insertion and deletion events have been identified causing a partial frame-shift that results in an altered amino acid sequence to that previously documented. TENP is conserved across divergent avian species being found in chicken, turkey, duck and zebra finch and its expression profile confirmed in both chicken and duck. Similarity searches have shown homology with the BPI-like family of innate immune genes, particularly with palate, lung and nasal epithelial clone (PLUNC) members of this family. We therefore believe that at least in adults the role of TENP is as a major component of egg, particularly the white and it is probable that it contributes to its antimicrobial function.
authors.affiliation: Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian EH25 9RG, UK. Electronic address: natasha.whenham@roslin.ed.ac.uk.
authors.forename: Natasha
authors.initials: N
authors.lastname: Whenham
authors.affiliation: Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian EH25 9RG, UK.
authors.forename: Peter W
authors.initials: PW
authors.lastname: Wilson
authors.affiliation: College of Medical, Veterinary and Life Sciences (MVLS), University of Glasgow, Glasgow, Scotland G61 1QGH, UK.
authors.forename: Maureen M
authors.initials: MM
authors.lastname: Bain
authors.affiliation: College of Medical, Veterinary and Life Sciences (MVLS), University of Glasgow, Glasgow, Scotland G61 1QGH, UK.
authors.forename: Lynn
authors.initials: L
authors.lastname: Stevenson
authors.affiliation: Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian EH25 9RG, UK.
authors.forename: Ian C
authors.initials: IC
authors.lastname: Dunn
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002642:Chick Embryo; D005260:Female; D018507:Gene Expression Regulation, Developmental; D012739:Gonadal Steroid Hormones / Q000494:pharmacology; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D009928:Organ Specificity; D010057:Oviducts / Q000378:metabolism; D011200:Poultry / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D012739:Gonadal Steroid Hormones; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; C111886:TENP protein, Gallus gallus
keywords: Antimicrobial protein; Avian; Chicken; Oviduct; PLUNC