Possibility of nonkinked packing of DNA in chromatin.
The idea that DNA in chromatin can be packed smoothly, without breaking of base-stacking interactions, has been explored by both energetical estimations and stereochemical model building. A model of deformed DNA is built that fits reasonably to the known dimensions of a nucleosome. The model has slightly changed torsion angles in the sugarphosphate moieties relative to B DNA, varying gradually along the chains. The angle between planes of adjacent base pairs varies between 1 and 7 degrees. This model of deformed DNA does not have any unusually close nonbonded contacts and is evidently not the only possible model of smooth packing of DNA in chromatin. An energetical estimation of the critical radius of curvature of a smoothly bent DNA molecule is made using approximate potential functions for different van der Waals contracts in the B DNA structure. The critical radius of curvature of the deformed DNA-axis is close to the radius of a nucleosome (similar to 50 A). The smooth packing is a good alternative to models of kinked folding of DNA in nucleosomes.
D002843:Chromatin / Q000648:ultrastructure*; D004247:DNA; D008961:Models, Structural; D009690:Nucleic Acid Conformation; D013816:Thermodynamics
D002843:Chromatin; D004247:DNA
J Mol Biol. 1961 Oct;3:547-65
14470668
Nucleic Acids Res. 1977;4(5):1159-81
331250
Proc Natl Acad Sci U S A. 1977 Apr;74(4):1458-62
266187
Proc Natl Acad Sci U S A. 1976 Dec;73(12):4382-6
826906
Nucleic Acids Res. 1976 Sep;3(9):2353-66
787935
Proc Natl Acad Sci U S A. 1976 Sep;73(9):3068-72
1067602
J Mol Biol. 1976 Nov 15;107(4):601-21
1003477
Cell. 1976 Nov;9(3):409-17
991271
Biophys Chem. 1976 Sep;5(3):301-18
987812
J Mol Biol. 1973 Aug 5;78(2):255-9
4747629
Adv Protein Chem. 1975;29:205-300
237413
J Mol Biol. 1968 Apr 14;33(1):173-97
4296518
Eur J Biochem. 1976 Apr 1;63(2):607-15
770176
Proc Natl Acad Sci U S A. 1975 May;72(5):1843-7
168578
J Mol Biol. 1974 Sep 15;88(2):523-33
4453006
Science. 1974 May 24;184(4139):868-71
4825889
Biochem Biophys Res Commun. 1972 Jun 28;47(6):1504-9
5040245
Biopolymers. 1970 Nov;9(11):1253-306
4922326
J Mol Biol. 1971 Jan 28;55(2):209-14
4926886
J Mol Biol. 1966 Oct 28;21(1):83-114
5338997
Adv Protein Chem. 1968;23:283-438
4882249
Nature. 1975 Jun 12;255(5509):530-3
1095931
J Mol Biol. 1976 Jun 14;104(1):109-44
957429
FEBS Lett. 1976 Apr 15;64(1):89-91
1269768
Nature. 1976 Jan 29;259(5541):333-5
1250371
Nature. 1975 Jan 24;253(5489):245-9
1167623
Cell. 1975 Apr;4(4):281-300
1122558
Nature. 1967 Jul 29;215(5100):508-9
6057909
J Mol Biol. 1967 Feb 14;23(3):523-33
6032188
Biopolymers. 1966 Apr-May;4(4):429-40
5948637
J Mol Biol. 1965 Dec;14(2):418-22
5880858
Nucleic Acids Res. 1974 Nov;1(11):1579-86
10793713