title: Metabolic proteomics of the liver and mammary gland during lactation.
abstract: The liver and the mammary gland have complementary metabolic roles during lactation. Glucose synthesized by the liver is released into the circulation and is taken up by the mammary gland where major metabolic products of glucose include milk sugar (lactose) and the glycerol backbone of milk fat (triglycerides). Hepatic synthesis of glucose is often accompanied by β-oxidation in that organ to provide energy for glucose synthesis, while mammary gland synthesizes rather than oxidizes fat during lactation. We have therefore compared enzyme abundances between the liver and mammary gland of lactating Friesian cows where metabolic output is well established. Quantitative differences in protein amount were assessed using two-dimensional differential in-gel electrophoresis. As predicted, the abundances of enzymes catalysing gluconeogenesis and β-oxidation were greatest in the liver, and enzyme abundances in mammary tissue were consistent with fat synthesis rather than β-oxidation.
authors.affiliation: Centre for Biodiscovery and School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand.
authors.forename: Pisana
authors.initials: P
authors.lastname: Rawson
authors.forename: Christine
authors.initials: C
authors.lastname: Stockum
authors.forename: Lifeng
authors.initials: L
authors.lastname: Peng
authors.forename: Bhagyashree
authors.initials: B
authors.lastname: Manivannan
authors.forename: Klaus
authors.initials: K
authors.lastname: Lehnert
authors.forename: Hamish E
authors.initials: HE
authors.lastname: Ward
authors.forename: Sarah D
authors.initials: SD
authors.lastname: Berry
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Davis
authors.forename: Russell G
authors.initials: RG
authors.lastname: Snell
authors.forename: Danyl
authors.initials: D
authors.lastname: McLauchlan
authors.forename: T William
authors.initials: TW
authors.lastname: Jordan
mesh_terms: D000818:Animals; D002417:Cattle / Q000378:metabolism*; D005260:Female; D007774:Lactation / Q000378:metabolism*; D008099:Liver / Q000378:metabolism*; D008321:Mammary Glands, Animal / Q000378:metabolism*; D009928:Organ Specificity / Q000502:physiology; D020543:Proteome / Q000378:metabolism*
chemical_list: D020543:Proteome