Genetic interaction between Non-MHC T- and B-cell alloantigens in response to rous sarcomas in chickens

Chickens of Regional Poultry Research Laboratory (RPRL) inbred line 6₃ regress sarcomas induced by Bryan high-titer Rous sarcoma virus to a greater extent than chickens of line RPRL 100, although these lines are identical for the major histocompatibility B complex. They differ, however, at three independent autosomal loci: Ly-4 and Th-1 determine the surface alloantigens of partly overlapping subsets of T lymphocytes, and Bu-1 determines a surface alloantigen of B lymphocytes. The association of genotypes at these loci with quantitative variation in their ability to regress Rous sarcomas was tested in segregating F₄ generation progeny derived from crosses of lines 100 and 6₃. The Ly-4 and Bu-1 genotypes showed association with Rous sarcoma regression, but the Th-1 genotype did not. Chickens of the Ly-4 ^a/Ly-4 ^a, Bu-1 ^b/Bu-1 ^b and Ly-4 ^b/Ly-4 ^b, Bu-1 ^a/Bu-1 ^a genotypes had a significantly higher regressor ability than the other two double homozygous genotypes. These results indicate that higher regression is associated with (1) interaction between the Ly-4 and Bu-1 loci, and (2) complementation between either the line 6 Ly-4 ^a allele and the line 100 Bu-1 ^b allele, or the line 100 Ly-4 ^b allele and the line 6 Bu-1 ^a allele.     

A spectroscopic analysis of the thermally induced folding-unfolding transition of beta-trypsin.

Absorption and fluorescence changes were used to monitor the thermally induced folding-unfolding transition of beta-trypsin. These parameters reflect changes in the microenvironment of different subsets of the four tryptophanyl residues of this protein. The thermal transition was found to be sequential.     

Peroxidase activity in human red cell: a biological model for excited state molecules generation.

The presence of enzymically generated triplet acetone in red cells and energy transfer to eosin, rose bengal and 9,10-dibromoanthracene-2-sulfonate was indicate by: (1) product distribution; (2) K_ET τ_o, similar to the 2-methylpropanal/peroxidase/O₂ system; (3) correlation between hemolysis, oxygen uptake and photon emission; (4) membrane protection by energy acceptors, and (5) by comparison of the 2-methylpropanal/peroxidase/O₂ system with 2-methylpropanal/red cells/membranes/O₂ and 2-methylpropanal/acid extractable protein from red cells membrane/O₂ systems, which have a high peroxidase activity.This is the first report of a biological system producing a photohemolysis effect in the dark.     

Inhibition of platelet phosphatidylinositol synthetase by an analog of CDP-diacylglycerol

Unpublished portions of the synthesis of a phosphinate-phosphonate diether analog of CDPdiacylglycerol are reported. The liponucleotide analog was found to be a very powerful inhibitor of platelet PI synthetase; kinetic data suggest a competitive inhibition mechanism. The structural specificity of CDPdiacylglycerol for liponucleotide-mediated biosynthetic reactions is discussed.