TY - JOUR
T1 - Biosynthetic studies on mannolipids and mannoproteins of normal and vitamin a-depleted hamster livers
AU - De Luca, Luigi M.
AU - Silverman-Jones, Carol S.
AU - Barr, Robert M.
N1 - Copyright:
Copyright 2014 Elsevier B.V., All rights reserved.
PY - 1975/12/17
Y1 - 1975/12/17
N2 - The incorporation of [1-14C] mannose into hamster liver glycolipids and glycoproteins was studied in normal and vitamin A-depleted hamsters. Severely (25% weight loss) and mildly (no weight loss) deficient animals were compared to vitamin A-fed controls. The incorporation of [14C] mannose into glycolipids and glycoproteins decreased in mild and severe vitamin A deficiency by 63-90% compared to vitamin A-fed animals. These results were essentially the same whether expressed per g of wet liver, per DNA or per protein. The size of the pools of mannose, glucose and galactose and their specific radioactivity in liver were determined by gas-liquid chromatography of the boronates of the hexitols (Eisenberg, Jr, F. (1972) Methods Enzymol. XXVIIIB, 168-178) in normal and vitamin A-deficient conditions. It was found that the amount of free hexoses per g of liver was very similar in normal and vitamin A-deficient conditions. The specific radioactivities for mannose and glucose were greater in vitamin A deficiency, thus excluding the possibility that the observed severe decrease in glycopeptide and glycolipid synthesis is a reflection of a similar decrease in the specific radioactivity of the precursor pools. Quantitation of mannose in glycoprotein showed a 79% decrease in vitamin A deficiency. Specific radioactivity of mannose in glycoproteins, 20 min after injection of the label, was 187 dpm/μg of mannose in the normal and 48 dpm/μg of mannose in the vitamin A-deficient livers. It is concluded that vitamin A is necessary for the biosynthesis of liver mannose-containing glycoproteins and glycolipids.
AB - The incorporation of [1-14C] mannose into hamster liver glycolipids and glycoproteins was studied in normal and vitamin A-depleted hamsters. Severely (25% weight loss) and mildly (no weight loss) deficient animals were compared to vitamin A-fed controls. The incorporation of [14C] mannose into glycolipids and glycoproteins decreased in mild and severe vitamin A deficiency by 63-90% compared to vitamin A-fed animals. These results were essentially the same whether expressed per g of wet liver, per DNA or per protein. The size of the pools of mannose, glucose and galactose and their specific radioactivity in liver were determined by gas-liquid chromatography of the boronates of the hexitols (Eisenberg, Jr, F. (1972) Methods Enzymol. XXVIIIB, 168-178) in normal and vitamin A-deficient conditions. It was found that the amount of free hexoses per g of liver was very similar in normal and vitamin A-deficient conditions. The specific radioactivities for mannose and glucose were greater in vitamin A deficiency, thus excluding the possibility that the observed severe decrease in glycopeptide and glycolipid synthesis is a reflection of a similar decrease in the specific radioactivity of the precursor pools. Quantitation of mannose in glycoprotein showed a 79% decrease in vitamin A deficiency. Specific radioactivity of mannose in glycoproteins, 20 min after injection of the label, was 187 dpm/μg of mannose in the normal and 48 dpm/μg of mannose in the vitamin A-deficient livers. It is concluded that vitamin A is necessary for the biosynthesis of liver mannose-containing glycoproteins and glycolipids.
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U2 - 10.1016/0005-2760(75)90030-2
DO - 10.1016/0005-2760(75)90030-2
M3 - Article
C2 - 1203251
AN - SCOPUS:0016830343
VL - 409
SP - 342
EP - 359
JO - BBA - Specialised Section On Lipids and Related Subjects
JF - BBA - Specialised Section On Lipids and Related Subjects
SN - 1388-1981
IS - 3
ER -