TitleGenomic imprinting of a placental lactogen gene in Peromyscus.
Publication TypeJournal Article
Year of Publication2001
AuthorsVrana, PB, Matteson, PG, Schmidt, JV, Ingram, RS, Joyce, A, Prince, KL, Dewey, MJ, Tilghman, SM
JournalDev Genes Evol
Date Published2001 Dec
KeywordsAmino Acid Sequence, Animals, Evolution, Molecular, Gene Expression, Genomic Imprinting, Hybridization, Genetic, Mice, Molecular Sequence Data, Multigene Family, Peromyscus, Phylogeny, Placenta, Placental Lactogen, Sequence Homology

The mammalian genome contains over 30 genes whose expression is dependent upon their parent-of-origin. Of these imprinted genes the majority are involved in regulating the rate of fetal growth. In this report we show that in the deer mouse Peromyscusthe placental lactogen-1-variant ( pPl1-v) gene is paternally expressed throughout fetal development, whereas the linked and closely related pPl1gene is expressed in a biallelic manner. Neither the more distantly related pPl2Agene, nor the Mus Pl1gene displays any preferential expression of the paternal allele, suggesting that the acquisition of imprinting of pPl1-v is a relatively recent event in evolution. Although pPl1 expression is temporally mis-regulated in the dysplastic placentae of hybrids between two Peromyscus species, its over-expression cannot account for the aberrant phenotypes of these placentae. We argue that the species-specific imprinting of pPl1-v, encoding a growth factor that regulates nutrient transfer from mothers to their offspring, is consistent with the parent-offspring conflict model that has been proposed to explain the evolution of genomic imprinting.

Alternate JournalDev. Genes Evol.