title: Promoter-specific expression of the imprinted IGF2 gene in cattle (Bos taurus).
abstract: The domestic cattle (Bos taurus) has been a good animal model for embryo biotechnologies, such as in vitro fertilization and nuclear transfer. However, animals produced from these technologies often suffer from large-calf syndrome, suggesting fetal growth disregulation. The product of the insulin-like growth factor 2 (IGF2) gene is one of the most important fetal mitogens known to date. A detailed analysis of age-, tissue-, and allele-specific expression of IGF2 has not been performed in the bovine mainly because the majority of the bovine sequence has been unavailable. In the present study, we obtained virtually the entire sequence of the bovine IGF2 cDNA, identified expressed single-nucleotide polymorphisms (SNPs) in both exons 3 and 10, and determined the age-, tissue-, and promoter-specific expression of bovine IGF2 in fetal, calf, and adult tissues. We found that, similar to the human and mouse, bovine IGF2 is subjected to extensive transcriptional regulation through multiple promoters, alternative splicing and polyadenylation, as well as genetic imprinting. However, major differences were found in the regulation of the bovine IGF2 in nearly all aspects of age-, tissue-, promoter-, and allele-specific expression of IGF2, and the promoter-specific loss of imprinting from every other species studied, including cattle's close relatives, the sheep and the pig. The data presented here are of important reference value to cattle produced from embryo biotechnologies.
authors.affiliation: Department of Animal Science/Center for Regenerative Biology, University of Connecticut, Storrs 06269, USA.
authors.forename: Carol
authors.initials: C
authors.lastname: Curchoe
authors.forename: Shouquan
authors.initials: S
authors.lastname: Zhang
authors.forename: Yanfang
authors.initials: Y
authors.lastname: Bin
authors.forename: Xiquan
authors.initials: X
authors.lastname: Zhang
authors.forename: Lan
authors.initials: L
authors.lastname: Yang
authors.forename: Dingyuan
authors.initials: D
authors.lastname: Feng
authors.forename: Michael
authors.initials: M
authors.lastname: O'Neill
authors.forename: X Cindy
authors.initials: XC
authors.lastname: Tian
mesh_terms: D000367:Age Factors; D017398:Alternative Splicing; D000818:Animals; D002417:Cattle / Q000235:genetics*; D018076:DNA, Complementary / Q000235:genetics; D005091:Exons; D005260:Female; D015870:Gene Expression; D005787:Gene Frequency; D018392:Genomic Imprinting; D007335:Insulin-Like Growth Factor II / Q000235:genetics*; D008297:Male; D009928:Organ Specificity; D026723:Polyadenylation; D020641:Polymorphism, Single Nucleotide; D011247:Pregnancy; D011401:Promoter Regions, Genetic; D017422:Sequence Analysis, DNA
chemical_list: D018076:DNA, Complementary; D007335:Insulin-Like Growth Factor II