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J L Winkelhake

Publications and source records attributed to J L Winkelhake.

47 records · Page 3Linked to original sources
PubMed1975

Studies on the mechanism of covalent incorporation of a lysergyl derivative to immunoglobulin peptides in vitro.

In vitro incubation of hyperimmune rabbit lymphoid cells with the hallucinogenic indole alkaloid, d-lysergic acid diethylamide (LSD), results in biosynthesis of modified, secretable immunoglobulin peptides. Modification involves covalent attachment of the lysergyl moiety to COOH-terminal portions of the peptides. Aalogous effects occur when cells are incubated in vitro in the presence of the non-hallucinogenic LSD analogue, d-lysergic acid, and N-[3H]-carboxymethyl-d-lysergamide. The phenomenon is reversed by tryptophan and is inhibited by puromycin and cycloheximide. In vitro attachment of the lysergyl moiety occurs in the presence of actinomycin D at levels which inhibit RNA synthesis. While LSD is not attached to intracellular tRNA, the drug binds to 80 S ribosomes from hyperimmune lymphoid cells with high affinity (K A equals 3.5 times 10-8 M-1). Similar binding occurs to nonimmune splenic ribosomes. Implications of these findings are discussed with respect to the degree of involvement of cellular protein translational mechanisms in the covalent attachment of the lysergyl moiety to low molecular weight immunoglobulin peptides.

Animals↗
PubMed1975

Cell surface changes and Rous sarcoma virus gene expression in synchronized cells.

We have investigated whether cell surface changes associated with growth control and malignant transformation are linked to the cell cycle. Chicken embryo cells synchronized by double thymidine block were examined for cell-cycle-dependent alterations in membrane function (measured by transport of 2-deoxyglucose, uridine, thymidine, and mannitol), in cell surface morphology (examined by scanning electron microscopy), and in the ability of tumor virus gene expression to induce a transformation-specific change in membrane function. We reach the following conclusions: (a) The high rate of 2-deoxyglucose transport seen in transformed cells and the low rates of 2-deoxyglucose and uridine transport characteristic of density-inhibited cells do not occur in normal growing cells as they traverse the cell cycle. (b) Although there are cell cycle-dependent changes in surface morphology, they are not reflected in corresponding changes in membrane function. (c) Tumor virus gene expression can alter cell membrane function at any stage in the cell cycle and without progression through the cell cycle.

Animals↗
PubMed1974

Mechanism of lysergic acid diethylamide interference with rabbit antibody biosynthesis.

Lymphoid cells from hyperimmune rabbits producing antibodies to a hapten, incubated in the presence of d-lysergic acid diethylamide, continued to synthesize protein at a normal rate. Isoelectric focusing analysis of the low-molecular-weight protein secreted by the cells incubated with lysergic acid diethylamide indicated two components, with pI's of 4.9 and 5.2. Immune cells not exposed to lysergic acid diethylamide secreted only 7S IgG molecules with an average pI of approximately 7.0.

Animals↗