title: Differences in expression and activity of beta,beta'-carotene-15,15'- oxygenase in liver and duodenum of cattle with yellow or white fat.
abstract: Pasture-fed cattle show yellow pigmentation of their fat due to beta-carotene stored in this tissue. beta,beta'-Carotene-15,15'-oxygenase (betaCO) is an enzyme expressed in different tissues, and it cleaves beta-carotene into retinal. We compared the expression and activity of betaCO in duodenum and liver of cattle with pigmented or non-pigmented fat. In the duodenum, in situ hybridizations showed expression of betaCO in epithelial cells and crypts of the mucosa that was similar in animals from pigmented and non-pigmented fat; liver showed diffuse signal at lobules, but pigmented animals showed higher signals near the portal space. Analyses by real-time reverse-transcription polymerase chain reaction also showed amplification of mRNA for betaCO in duodenum and liver, with no difference between pigmented or non-pigmented animals. Enzyme activity was similar in the duodenum, but pigmented animals had higher enzyme activity (p = 0.004) in liver. Cattle with pigmented fat had higher expression and activity of betaCO in liver, but its level was not high enough to prevent the storage of beta-carotene in adipose tissues.
authors.affiliation: Facultad de Estudios Superiores-Cuautitlán, Universidad Nacional Autónoma de México, Queretaro, Qro, Mexico.
authors.forename: A
authors.initials: A
authors.lastname: Morales
authors.forename: A
authors.initials: A
authors.lastname: González
authors.forename: A
authors.initials: A
authors.lastname: Varela-Echavarría
authors.forename: A
authors.initials: A
authors.lastname: Shimada
authors.forename: O
authors.initials: O
authors.lastname: Mora
mesh_terms: D000273:Adipose Tissue / Q000737:chemistry / Q000378:metabolism*; D000821:Animal Feed; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D002417:Cattle; D004386:Duodenum / Q000201:enzymology*; D015971:Gene Expression Regulation, Enzymologic; D017403:In Situ Hybridization; D008099:Liver / Q000201:enzymology*; D010858:Pigmentation; D006109:Poaceae; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D019207:beta Carotene / Q000008:administration & dosage / Q000378:metabolism; D050559:beta-Carotene 15,15'-Monooxygenase / Q000235:genetics / Q000378:metabolism*
chemical_list: D019207:beta Carotene; D050559:beta-Carotene 15,15'-Monooxygenase