Susanne Höpfner (PhD)

Project C2 & C3: 

The role of DLCs and AGO proteins in NAT-lncRNA mediated regulation of gene expression and plant immunity 

Susanne studied biochemistry at the Martin-Luther-University Halle-Wittenberg. As a PhD student she analyzes the role of the natural antisense long non-coding RNA (NAT-lncRNA) encoded by At4g14548 (NAT-IAA14) in IAA14 expression. NAT-lncRNAs are transcribed from the opposite strand of a coding gene but have no protein-coding capacity by itself.

In vivo studies showed that NAT-IAA14 and IAA14 are co-expressed in seedlings of Arabidopsis thaliana at the full-expanded cotyledons stage and that, at least for IAA14, the 3’end is longer as reported in the Arabidopsis Information Resource (TAIR) database. Furthermore an overlapping intergenic region of these two transcript RNAs was identified. The presence of opposite complementary, overlapping RNAs produces dsRNA molecules which can be recognized by the silencing machinery of the plant. The thereby processed small interfering RNAs, called cis-NAT-siRNAs, are able to regulate the expression of genes via posttranscriptional gene silencing.

We aim to determine the role of NAT-IAA14 in the regulation of IAA14. Through an established in vitro system of cytoplasmic extract of evacuolated Nicotiana tabacum BY2 protoplasts (BYL) we expect to identify the AGO proteins involved in RISC-mediated cleavage of target RNAs and additionally the thereby produced siRNAs that are efficient for target(s) downregulation. These siRNAs will be validated in vivo using A. thaliana mutants. Furthermore we want to define the processes in which NAT-IAA14 is involved and to decipher the regulatory network subjacent to its action.


Supervisors: Prof. Dr. Sven-Erik Behrens and Dr. Selma Gago Zachert



Phone: +49-(0)345 5524906 (MLU: Microbial Biotechnology)

           +49-(0)345 55821224 (IPB: Molecular Signal Processing)

E-mail: susanne.hoepfner(at)