DNA topoisomerases are enzymes that disentangle the topological problems that arise in
double-stranded DNA. Many of these can be solved by the generation of either single or …

Growth factors, a diverse group of polypeptides that modify cell proliferation, constitute a
distinct subgroup in endocrinology. The biology of these factors differs somewhat from …

Type II topoisomerases are ubiquitous enzymes in all branches of life that can alter DNA
superhelicity and unlink double-stranded DNA segments during processes such as …

INTRODUCTION The faithful replication and segregation of chromosomes as part of the cell
division cycle requires that topological changes be imposed upon cellular DNA …

The first two enzymes capable of catalyzing the phosphorylation of proteins were detected in
the fifties [1-3], through quite different approaches. The discovery of phosphorylase kinase …

Our understanding of the structure and function of mitotic chromosomes has come a long
way since these iconic objects were first recognized more than 140 years ago, though many …

We have used an antibody probe to measure the levels of topoisomerase II in several
transformed and developmentally regulated normal cell types. Transformed cells contain …

We have utilized antibody probes to examine the expression of DNA topoisomerases I and II
and chromosome scaffold protein Sc-2 in normal and transformed cells. Neither …

Topoisomerase II was purified from an amsacrine-resistant mutant of P388 leukemia. A
procedure has been developed which allows the rapid purification of nearly homogeneous …

The specificity of casein kinase II has been further defined by analyzing the kinetics of
phosphorylation reactions using a number of different synthetic peptides as substrates. The …