Evidence map›Paper›PMID 26001583›Full record

ArticleBMC bioinformatics2015

Probing long-range interactions by extracting free energies from genome-wide chromosome conformation capture data.

Saeed Saberi, Pau Farré, Olivier Cuvier, Eldon Emberly

Abstract read
In one paragraph

Article in BMC bioinformatics, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

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2 · The registry

The trial behind it

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed.

  1. Article
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4 · The record

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PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

4 authors.

Saeed SaberiPhysics Department, Simon Fraser University, 8888 University Drive, Burnaby, V5A 1S6, BC, Canada. saied.sabery.m@gmail.com.
Pau FarréPhysics Department, Simon Fraser University, 8888 University Drive, Burnaby, V5A 1S6, BC, Canada. pau557@gmail.com.
Olivier CuvierLaboratoire de Biologie Moléculaire des Eucaryotes (LBME), Toulouse, France. olivier.cuvier@ibcg.biotoul.fr.
Eldon EmberlyPhysics Department, Simon Fraser University, 8888 University Drive, Burnaby, V5A 1S6, BC, Canada. eemberly@sfu.ca.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundA variety of DNA binding proteins are involved in regulating and shaping the packing of chromatin. They aid the formation of loops in the DNA that function to isolate different structural domains. A recent experimental technique, Hi-C, provides a method for determining the frequency of such looping between all distant parts of the genome. Given that the binding locations of many chromatin associated proteins have also been measured, it has been possible to make estimates for their influence on the long-range interactions as measured by Hi-C. However, a challenge in this analysis is the predominance of non-specific contacts that mask out the specific interactions of interest.

resultsWe show that transforming the Hi-C contact frequencies into free energies gives a natural method for separating out the distance dependent non-specific interactions. In particular we apply Principal Component Analysis (PCA) to the transformed free energy matrix to identify the dominant modes of interaction. PCA identifies systematic effects as well as high frequency spatial noise in the Hi-C data which can be filtered out. Thus it can be used as a data driven approach for normalizing Hi-C data. We assess this PCA based normalization approach, along with several other normalization schemes, by fitting the transformed Hi-C data using a pairwise interaction model that takes as input the known locations of bound chromatin factors. The result of fitting is a set of predictions for the coupling energies between the various chromatin factors and their effect on the energetics of looping. We show that the quality of the fit can be used as a means to determine how much PCA filtering should be applied to the Hi-C data.

conclusionsWe find that the different normalizations of the Hi-C data vary in the quality of fit to the pairwise interaction model. PCA filtering can improve the fit, and the predicted coupling energies lead to biologically meaningful insights for how various chromatin bound factors influence the stability of DNA loops in chromatin.

Indexed as

GenomeNucleic Acid ConformationAnimalsChromatinChromosome MappingChromosomesDNADrosophila melanogasterMolecular ConformationPrincipal Component AnalysisChromatinDNA

Identifiers

PMID26001583
PMCPMC4492175

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.