Studies on the decondensation of human, mouse, and bull sperm nuclei by heparin and other polyanions.

摘要: We report heparin-induced decondensation of human, mouse, and bull sperm nuclei. Decondensation did not occur if the spermatozoa were intact but only membranes severely damaged by freezing thawing or treatment with a detergent. If disulphide bond reducing agent (thiol) was absent, human nuclei usually relatively slow process, large interindividual variation. Mouse decondense in absence thiol. With thiol low concentrations heparin induced rapid all three species. The activity specific for heparin; other polyanions also active, being most effective compound. It is supposed that induce nuclear because they deplete protamines from chromatin. Thus negatively charged phosphate groups DNA are no longer opposed positively protamines. Consequently mutual repulsion unopposed causes molecules to stretch, which results an increase volume. Since under physiological pH temperature, might be active oocyte.