title: Evolution of Pinnipedia lactation strategies: a potential role for alpha-lactalbumin?
abstract: Despite the considerable variation in milk composition found among mammals, a constituent common across all groups is lactose, the main sugar and osmole in most eutherians milk. Exceptions to this are the families Otariidae (fur seals and sea lions) and Odobenidae (walruses), where lactose has not been detected. We investigated the molecular basis for this by cloning alpha-lactalbumin, the modifier protein of the lactose synthase complex. A mutation was observed which, in addition to preventing lactose production, may enable otariids to maintain lactation despite the extremely long inter-suckling intervals during the mother's time at sea foraging (more than 23 days in some species).
authors: CRC for Innovative Dairy Products, Department of Zoology, University of Melbourne, Victoria 3010, Australia.
authors: Coralie M
authors: CM
authors: Reich
authors: John P Y
authors: JP
authors: Arnould
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D010872:Caniformia / Q000235:genetics / Q000502:physiology*; D007768:Lactalbumin / Q000235:genetics*; D007774:Lactation; D008969:Molecular Sequence Data
chemical_list: D007768:Lactalbumin
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