title: Porcine amelogenin is expressed from the X and Y chromosomes.
abstract: Amelogenin is the major enamel matrix component in developing teeth. In eutherian mammals, amelogenin is expressed from the X chromosome only, or from both the X and Y chromosomes. Two classes of porcine amelogenin cDNA clones have been characterized, but the chromosomal localization of the gene(s) encoding them is unknown. To determine if there are sex-based differences in the expression of porcine amelogenin, we paired PCR primers for exons 1a, 1b, 7a, and 7b, and amplified enamel organ-derived cDNA separately from porcine males and females. The results show that exons 1a/2a and 7a are always together and can be amplified from both males (XY) and females (XX). Exons 1b/2b and 7b are also always paired, but can be amplified only from females. We conclude that porcine amelogenin is expressed from separate genes on the X and Y chromosomes, and not, as previously proposed, from a single gene with two promoters.
authors.affiliation: Department of Biochemistry, School of Dental Medicine, Tsurumi University, 2-1-3 Tsurumi, Tsurumi-ku, Yokohama, 230-8501, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ikawa
authors.forename: A
authors.initials: A
authors.lastname: Kakegawa
authors.forename: T
authors.initials: T
authors.lastname: Nagano
authors.forename: H
authors.initials: H
authors.lastname: Ando
authors.forename: Y
authors.initials: Y
authors.lastname: Yamakoshi
authors.forename: T
authors.initials: T
authors.lastname: Tanabe
authors.forename: J P
authors.initials: JP
authors.lastname: Simmer
authors.forename: C-C
authors.initials: CC
authors.lastname: Hu
authors.forename: M
authors.initials: M
authors.lastname: Fukae
authors.forename: S
authors.initials: S
authors.lastname: Oida
mesh_terms: D053523:Amelogenin; D000818:Animals; D002874:Chromosome Mapping; D003746:Dental Enamel Proteins / Q000235:genetics* / Q000378:metabolism; D004658:Enamel Organ / Q000378:metabolism*; D005091:Exons / Q000235:genetics; D005260:Female; D007180:Incisor; D008297:Male; D008334:Mandible; D012313:RNA / Q000032:analysis; D012737:Sex Factors; D013552:Swine; D014083:Tooth Germ / Q000378:metabolism*; D014960:X Chromosome / Q000235:genetics / Q000378:metabolism*; D014998:Y Chromosome / Q000235:genetics / Q000378:metabolism*
chemical_list: D053523:Amelogenin; D003746:Dental Enamel Proteins; D012313:RNA