| Abstract: | The effect on the blood serum of patients with Down's syndrome and of healthy persons and also separate fractions of sera on structural parameters of model nucleohistone systems (DNP-systems) was studied. Unfractionated patients' sera were found to have a condensing effect on DNP-systems, unlike healthy human sera. Analysis of the action of the individual serum fractions showed that different degrees of condensation can be attributed to the influence of high-molecular weight, undialyzable, thermolabile components, the action of which disappears after gel-filtration of the serum proteins. The problem of possible humoral control over the structural organization of chromatin in vivo is discussed in the light of data showing similarity between blood serum proteins and certain nonhistone proteins of chromatin.Laboratory of Molecular Biology, Institute of Medical Genetics, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. P. Bochkov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 10, pp. 460–463, October, 1979. |
