institute of gene biology ras, moscow russia. · 2015. 8. 6. · adapted from lieberman-aiden et...
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Adapted from Lieberman-Aiden et al., Science 326 (5950):289, D. Pons et al., Euro. Heart Journal, 2009
Block-copolymer model of chromatin organization
Conclusions
Pavel I. Kos1, Alexey A.Gavrilov2, Alexander V. Chertovich1 1Physics Department, Lomonosov Moscow State University, Moscow, Russia
2 Institute of Gene Biology RAS, Moscow Russia. *[email protected]
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Introduction Block-copolymer results
Normal volume interactions
Saturating
interactions
TAD
•Saturating interactions present smoothed coil-to-globule transition with long-lived intermediate
states.
•TAD partitioning can be explained by different modes of inter- nucleosomal interactions for active
and inactive chromatin.
10 20 30 40 50 60 70 80
0,00
0,05
0,10
0,15
0,20
0,25 500
100
Created Bonds / All possible Bonds, %
Rg
2/N
1 10 100 1000 10000
0,1
1
10
100
1000
Sp
atia
l d
ista
nce
sq
ua
red
Distance along the chain
70%
42%
21%
Start Conformation
~1
~2/3
1 10 100 1000 10000
1E-6
1E-5
1E-4
1E-3
0,01
0,1
1
10
Conta
ct pro
babili
ty
Distance along the chain
Regular volume interactions
Saturating interactions
Only bonded beads
-3/2
We introduce saturating interactions to
mimic sticking of inactive chromatin
Homopolymer chain
Globule
«Swollen» globule
Saturated bonds statistics is Gaussian-like
Transition point is about 25% percents
of all possible bonds, but the globule
is not dense.