Non-histone proteins in mononucleosomes and subnucleosomes [laboratory animals]

Nucleosomes and subnucleosomes separated either by sucrose gradient ultracentrifugation or by polyacrylamide gel electrophoresis contain proteins incorporating [3H]tryptophan, i.e. non‐histone proteins. The fractions of mononucleosomes MN3 and MN2 are enriched in these proteins as compared to the MN...

Full description

Saved in:
Bibliographic Details
Published in:European journal of biochemistry Vol. 91; no. 1; pp. 291 - 301
Main Authors: BAKAYEV, Valery V., BAKAYEVA, Tamara G., SCHMATCHENKO, Vadim V., GEORGIEV, Georgii P.
Format: Journal Article
Language:English
Published: Oxford, UK Blackwell Publishing Ltd 02-11-1978
Subjects:
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Nucleosomes and subnucleosomes separated either by sucrose gradient ultracentrifugation or by polyacrylamide gel electrophoresis contain proteins incorporating [3H]tryptophan, i.e. non‐histone proteins. The fractions of mononucleosomes MN3 and MN2 are enriched in these proteins as compared to the MN1 fraction. Two‐dimensional gel electrophoresis of chromatin digests reveals a number of non‐histone proteins comigrating with deoxyribonucleoprotein particles in the first direction (in non‐dissociating conditions). A significant fraction of these proteins corresponds to basic non‐histone proteins, so‐called HMG (high‐mobility‐group) proteins. Two HMG proteins are present in mononucleosomes MN3 exclusively and three others in mononucleosomes MN3 and MN2. One of them is recovered also in subnucleosomes SN2, and another in SN3 subnucleosome fraction, At least three HMG proteins are rapidly released from the oligonucleosome fractions as well as from the insoluble DNA protein residue. Thus, they are located in chromatin readily available to DNAase action. Apart from HMG proteins, a number of other non‐histone proteins are present in mononucleosomes but their relative content in the oligonucleosome fraction is much higher. The conclusion has been drawn that many non‐histone proteins, in particular HMG proteins, interact with linker DNA in chromatin.
Bibliography:L
L40
Proc. Acad. Sci. U.S.S.R.
Recently we found that DNA prepared from SN2 particles hybridizes to much higher extent with nuclear heterogeneous RNA (Bakayev, V. V., Schmatchenko, V. V. & Georgiev, G. P.
in the press). This result supports the idea that HMG‐G is located in the transcribed chromatin fractions.
Note Added in Proof
ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 23
ISSN:0014-2956
1432-1033
DOI:10.1111/j.1432-1033.1978.tb20965.x