Metabolic proteomics of the liver and mammary gland during lactation

Centre for Biodiscovery and School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand.
Journal of proteomics (Impact Factor: 3.89). 04/2012; 75(14):4429-35. DOI: 10.1016/j.jprot.2012.04.019
Source: PubMed


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.

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    • "Basic transcription factor 3 (BTF3) is over represented during the mouse mammary development which plays an important role in alveolar growth during pregnancy while minichromosome maintenance complex component 3 (MCM3) has been identified as a marker of progenitor cells during lactation and post-lactation period [15]. Metabolic proteome using two-dimensional gel electrophoresis (2DE) of mammary gland tissue during lactation has been reported in Bos taurus and their role in carbohydrate and lipid metabolism has been described in greater detail [16] [17]. However, no systematic studies have been reported in B. bubalis (Water buffalo) during pubertal stage and different stages of lactation. "
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