报告题目：Universal Sequence Encoding of an Accessible Nucleosomal Chromatin Fiber across Vertebrates
报告人：Benjamin Audit 研究员
主持人：张三军 研究员
时间：2018-1-5 9:30
地点：理科大楼A814
报告人简介：
Benjamin Audit为法国CNRS科研主任，里昂高等师范大学物理实验室研究员，国际知名的基因组学专家，BMC Bioinformatics期刊副主编。
October 2014 Director of Research at Centre National de la Recherche Scientifique (CNRS).
November 2012 Diploma of “Habilitation `a diriger des Recherches” (HDR, accreditation to supervise research) (ENS de Lyon) : Multi-scale analysis of the mammalian replication programme.
November 2003 Research Associate at Centre National de la Recherche Scientifique (CNRS).
Research unit: Laboratoire de Physique of ENS-Lyon (UMR5672). Associated to Laboratoire Joliot-Curie in 2003–2010 and member of LJC resident team during 2011.
2000-2003 Post-doctorate at the European Bioinformatics Institute (EMBL-EBI) (Christos Ouzounis, Computational Genomics Group).
Marie Curie fellowship for the project: Global measures for genome structure and evolution (2001-2003).
1996-2000 PhD Thesis: “Statistical analysis of DNA sequences using the wavelet transform”.
Supervisor: Prof. Alain Arneodo.
Centre de Recherche Paul Pascal, University of Bordeaux, France.
1994-1995 Diplome d’ Etude Approfondie (Champs Particules Matieres), University of Paris VI. Equivalent to a Master of Science.
1992-1995 Diplome de l’ Ecole Superieure d’Electricite (Supelec).
Equivalent to a Master in Engineering.
报告内容简介：
We recently shown that nucleosome depleted regions (NDRs) around which nucleosomes crystallise following the “statistical” positioning scenario are encoded in the DNA sequence in human. This intrinsic nucleosomal ordering strongly correlates with oscillations in the local GC content as well as with the interspecies and intraspecies mutation profiles revealing the existence of both positive and negative selection. We will show that these predicted nucleosome inhibitory energy barriers (NIEBs) with compacted neighbouring nucleosomes are indeed ubiquitous to all vertebrates tested. These 1 kb-size chromatin patterns are widely distributed along vertebrate chromosomes overall covering more than a third of the genome. These genome-wide distributed deviations from neutral evolution have been interpreted as a possible indication of the selection of an open accessible and dynamic 10 nm chromatin fibre to constitutively facilitate the epigenetic regulation of nuclear functions in a cell-type specific manner. As a first very appealing observation supporting this hypothesis, we will present evidence of a strong association between NIEBs borders and the poly(A) tails of Alu sequences in human. These results suggest that NIEBs provide adequate chromatin patterns favourable to the integration of Alu retrotransposons and more generally to various transposable elements (TEs) in primates and other vertebrate genomes.