ISOLATION OF A NUCLEAR RNA FRACTION RESEMBLING DNA IN ITS BASE COMPOSITION

A REVERSIBLY CONTRACTILE NUCLEAR MATRIX Its Isolation, Structure, and Composition

From Tetrahymena macronuclei we have isolated a reversibly contractile nucleoskeleton, i.e., an "expanded" nuclear matrix which reversibly contracts when the total concentration of the bivalent cations, Ca and Mg (3:2), is decreased to 5 mM or increased to 125 raM. During contraction the average diameter of the expanded matrix becomes reduced by about 24%; this corresponds to a volume contracti...

Reversibly contractile nuclear matrix. Its isolation, structure, and composition

From Tetrahymena macronuclei we have isolated a reversibly contractile nucleo-skeleton, i.e., an "expanded" nuclear matrix which reversibly contracts when the total concentration of the bivalent cations, Ca and Mg (3:2), is decreased to 5 mM or increased to 125 mM. During contraction the average diameter of the expanded matrix becomes reduced by about 24%; this corresponds to a volume contracti...

Base Composition of High Molecular Weight Nuclear Rna of Walker Tumor and Liver of the Rat.

Isolation of circular DNA from a mitochondrial fraction from yeast.

Breakage and fractionation of respiratory competent yeast in the presence of ethidium bromide, and subsequent centrifugation of a detergent lysate of the mitochondrial fraction by the dye-buoyant-density technique, results in the isolation of closed-circular DNA. After removal of bound dye, this DNA has two components when analyzed by equilibrium buoyant density in the analytical ultracentrifug...

The isolation of complementary strands from a mouse DNA fraction.

The nuclear DNA from all mouse strainsl-6 and mouse tissue" 2 thus far investigated exhibits two DNA bands when centrifuged to equilibrium in a CsCl density gradient. The principal band, which comprises 90 per cent of the nuclear DNA, is found at a buoyant density 0.01 gin cm-3 higher than the minor component, or satellite band, as it is generally called. Not only is this satellite DNA remarkab...