title: Pheomelanin coat colour dilution in French cattle breeds is not correlated with the TYR, TYRP1 and DCT transcription levels.
abstract: In this study we report the isolation of full-length cDNAs and the expression patterns of TYR, TYRP1 and DCT in four e/e cattle breeds exhibiting different pheomelanic coat colours ranging from reddish brown to creamy white phenotypes. Predicted proteins encoded by bovine TYR, TYRP1 and DCT display high levels of homology and contain all characteristic domains shared between their mouse and human counterparts. The full expression of these three genes is observed in melanocytes of black areas of E(D)/E(D) Prim'Holstein's animals. On the other hand, e/e melanocytes of animals belonging to the Blonde d'Aquitaine (blond), Limousine (red) and Salers (reddish brown) breeds present different levels of down-regulated TYR and DCT expression and a complete repression of TYRP1. Surprisingly, e/e melanocytes of animals belonging to the Charolais breed (creamy white) present an inverse relationship between TYR, TYRP1 and DCT expression and its lower melanogenic activity. The sum of these results shows that the dilution of the coat colour in French cattle breeds is not correlated with a transcription level of TYR family genes. Other possible modifier loci are suggested.
authors.affiliation: Unité de Génétique Moléculaire Animale, UMR1061 INRA/Université de Limoges, Limoges, France.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Guibert
authors.forename: Michael
authors.initials: M
authors.lastname: Girardot
authors.forename: Hubert
authors.initials: H
authors.lastname: Leveziel
authors.forename: Raymond
authors.initials: R
authors.lastname: Julien
authors.forename: Ahmad
authors.initials: A
authors.lastname: Oulmouden
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002417:Cattle / Q000235:genetics*; D018076:DNA, Complementary / Q000378:metabolism; D015870:Gene Expression; D006200:Hair Color / Q000235:genetics*; D006801:Humans; D019746:Intramolecular Oxidoreductases / Q000235:genetics / Q000378:metabolism; D008543:Melanins / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D014442:Monophenol Monooxygenase / Q000235:genetics / Q000378:metabolism; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D016415:Sequence Alignment; D014158:Transcription, Genetic
chemical_list: D018076:DNA, Complementary; D008543:Melanins; C018362:pheomelanin; D010088:Oxidoreductases; C064056:tyrosinase-related protein-1; D014442:Monophenol Monooxygenase; D019746:Intramolecular Oxidoreductases; C042501:dopachrome isomerase