[Forschungsseminar-BSV] Forschungsseminar Computergrafik, Bildverarbeitung und Visualisierung

[Patrick Oesterling]

E I N L A D U N G

zum Forschungsseminar 'Computergrafik, Bildverarbeitung und 
Visualisierung' am Mittwoch, den 07. Januar 2015, 13:15 Uhr, Raum P-701 
im Paulinum am Augustusplatz.


Wir hören einen Vortrag von:

Daniel Gerighausen
Bioinformatik
Institut für Informatik
Universität Leipzig

mit dem Titel

"Tibi-3D - a Guide through the World of Epigenetics "


zum Inhalt:

In the last two decades the study of changes in the genome function that 
are not induced by changes in DNA has consolidated a strong research 
field called ”epigenetics”. Chromatin state changes play an essential 
role in the regulation of transcription of many genes, thus controlling 
cell differentiation. A large part of these changes is due to histone 
modifications that alter the accessibility of the DNA. Current state of 
the art visualization methods for the analysis of epigenetic data sets 
are not suited to represent the relationship between the combinatorial 
pattern of histone modifications and their regulatory effects. A recent 
strategy to generate a global overview of these interactions is the use 
of scatterplots. One of the biggest weaknesses of scatterplots is the 
overplotting. This can be solved using a 2D tiled-binned representation 
strategy, where dividing scatterplot into bins consisting of tiles for 
each modification pattern is possible. However, this 2D strategy does 
not allow to represent the interaction of more than two histone 
modifications. Here, TiBi-3D, a tool that can visualize the 
combinatorics of histone modifications with tiled-binned 3D 
scatterplots, is presented. Two important features of TiBi-3D are that 
tiles are represented with spheres in the scatterplot, and that their 
position and color encodes the histone modification pattern they 
represent. TiBi-3D also includes a transparency value assigned to each 
of that spheres to depict the amount of data points in each bin. In 
addition, to reduce the occlusion in the scatterplot each transparency 
value is initially filtered by an outlier detection, transformed to log 
scale, and then normalized. TiBi-3D provides features for exploration 
and interaction with the scatterplot and the data, thus enabling to 
examine the data set thoroughly. It is also possible to export the 
results as figures or in bed file format for further processing. By 
using TiBi-3D, for example, it was possible to observe new relations 
between the CpG-density and histone modifications in different cell 
types. In conclusion, TiBi-3D is a excellent tool for the analysis of 
global patterns in epigenetic data.


Alle Interessierten sind im Namen von Professor Dr. Scheuermann herzlich 
eingeladen.

Mit freundlichen Grüßen,
Patrick Oesterling