BikF


Maria Nilsson-Janke

Co-supervised PhD students
Susanne Gallus
Fritjof Lammers

PhD students from external universities
William Dodt, QUT, Australia
 

Dr. Maria Nilsson-Janke

Researcher

D1.6: Transposable elements evolutionary genomics

Research

My research focus is on the dynamics of mobile genetic elements, in particular transposable elements in mammalian genomes.
 
What is a transposable element?
Transposable elements (TEs) are typically 300 to 6000 nucleotides long sequences that occur in multiple copies and make up 40-50% of the mammalian genome. They are present in all eukaryotes. TEs are divided into two classes, the retrotransposons and the DNA transposons. Common to the two classes is their ability to move around in the genome (“jumping genes”). Retrotransposons use a ‘copy-and-paste’ approach of an RNA intermediate and can thus multiply a million-fold by “pasting” new copies into the genome in a short time frame. To date there is no biochemical removal mechanism described. Therefore, every new copy in a genome will remain as a silent fossil, as an evidence for an integration event.
 
Transposable elements as unique relationship markers
TEs in the genome are inherited to all descendants and are thus an ideal marker system to resolve evolutionary questions. The genetic properties of TE inheritance make it a marker system that is independent from morphological or sequence analyses and offers a third way to resolve the phylogenetic history. The strength of TEs as evolutionary markers is that they are not affected by adaption such as morphological characters, and have virtually unlimited character states compared to traditional sequence analysis.
 
The ‘biodiversity’ of TEs in mammalian genomes
More than 500 different types of TEs, are known from the human genome. They are evolving in an intricate balance with the host genome. The interchange between different transposable elements within the host genome can be seen as a genomic ecosystem. As in natural ecosystems, introduction or extinction of transposable elements can have dramatic long-term effects on the genome, among others: causing disease, morphological changes, and adaptations.
The human genome and its transposable elements are being studied in detail, because of the medical implications. However, the genomes of other mammalian genomes are currently ‘black boxes’. Therefore, we study the impact of transposable elements on genome structure and composition in several distantly related mammalian groups.

Selected recent publications:

Nilsson, MA. (2015) The devil is in the details: transposable element analysis of the Tasmanian devil genome. Mobile Genetic Elements. Gene

Gallus, S, Kumar, V, Bertelsen, MF, Janke, A, Nilsson, MA. (2015) A genome survey sequencing of the Java mouse deer (Tragulus javanicus) adds new aspects to the evolution of lineage specific retrotransposons in Ruminantia (Cetartiodactyla). Gene, 571(2):271-8.

Gallus, S, Kumar, V, Janke, A, Nilsson, MA. (2015) Disentangling the relationship of the Australian marsupial orders using retrotransposon and evolutionary network analyses. Genome Biol Evol. 7(4):985-92

CV

2011- Post Doc Senckenberg
2010 Post Doc Lund University, Sweden
2007-2009 Post Doc Muenster University, Germany
2001-2006 PhD Lund University, Sweden

Publications

Contact
Phone: +49 (0)69 7542 1829
E-Mail