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Prof. Dr. rer. nat. G. Sczakiel          
Institut für Molekulare Medizin
UK S-H, Campus Lübeck • Universität zu Lübeck
Center for Structural and Cell Biologie in Medicine, CSCM
23538 Lübeck • Ratzeburger Allee 160
Startbild
 
tel.: (+49 451) 500-50801
fax.: (+49 451) 500-50804
 
sczakiel@imm.uni-luebeck.de
 
 
           





     
Dornseifer, Simon dornseifer@imm.uni-luebeck.de (+49 451) 500-50831  
Lamm, Patrick lamm@imm.uni-luebeck.de (+49 451) 500-50831  
Neubert, Juliane neubert@imm.uni-luebeck.de (+49 451) 500-50831  





Topics include
 
   • Structure-function relationship of RNA-RNA recognition
   • delivery of oligomeric nucleic acids drugs (aptamers, antisense, siRNA, miRNA)
   • mechanism of RNA interference
   • biology of extracellular RNA in vivo including RNA-based non-invasive tumor diagnostics

Controlled expression of genetic information is crucial to normal development of cells and organisms. In the course of regulated gene expression from genes via gene products to phenotypes, nucleic acids represent two major classes of natural macromolecules, deoxyribonucleic acids (DNA) and ribonucleic acids (RNA), respectively. Dysregulated or aberrant gene expression, however, may lead to altered phenotypes including uncontrolled cell proliferation or functional defects that may be causatively related to diseases.

As the human genome and its transcribed sequences become increasingly revealed more light is shed onto the molecular level of the pathomechanisms of human diseases which may include fatal changes of DNA and, hence, RNA transcribed thereof. At this level, the analysis of genomic DNA and of transcribed sequences including mRNA (transcriptome) enables one in principle to obtain diagnostic information on the risk or state of human diseases. As uncontrolled and also viral gene expression may cause the development of serious diseases including cancer and lethal infections such as AIDS, specific DNA segments and mRNAs represent new and promising drug targets for novel therapeutic concepts on the molecular level. Interestingly, short nucleic acids (oligonucleotides) may be used to interfere with the biological function of DNA and RNA and several classes of oligonucleotides are currently under investigation as new drugs. Oligonucleotides are synthesized by chemical means. They are not expressed endogenously and, thus, have to be delivered to target cells and target tissues in vivo which requires new methodologies for the cellular uptake. The studies are performed at the levels of biochemistry, molecular biology, and cell biology. In collaboration with clinical partners, we also conduct pre-clinical studies and studies in vivo.

 
 
Quantitative RNA cell biology – delivery of siRNA
 
Controlled The cellular delivery of siRNA is one of the major technical hurdles of its application in living cells. A new route of cellular uptake a caveolae-mediated intra-celluar translocation may provide alternative optinios for the efficient application of siRNA







 


Cells harbouring biologically active siRNA in vesicles (orange, indicated by a white arrow), delivered according to a novel phosphorothioate-based principle  (Overhoff & Sczakiel, 2005).
 
 
Array-based search for target-specific hexanucleotides
 
Controlled A novel chip design was developed in which the complete sequence space of hexanucleotides is printed. This approach enables a systematic array-based search for hexanucleotides which specifically and tightly bind to any target of interest thereby leading to lead compounds for subsequent drug development. The enormous target selectivity of this method is reflected by species that distinguish between the highly conserved reverse transcriptases (RT) of HIV-1 and HIV-2.



















Hexanucleotide array. The signal pattern observed in the use of closely related target proteins is different and shows the high specificity of the array-based system
 
 
Molecular diagnostics
 
The existence of RNA outside cells (exRNA) is known for a long time. The presence and amounts of individual extracellular RNA species are correlated to the extent of necrosis and apoptosis. In vivo, some of these exRNAs bind to blood cells thereby “travelling” through the human organism. Surprisingly, extracts containing extracellular nucleic acids derived from tumour cells have been shown to induce tumour growth in vivo. Therefore, exRNAs provide a diagnostic as well as therapeutic target.

We apply methods from molecular biology, cell biology as well as biochemistry to investigate mode of action of these exRNA molecules. A beneficial application of these investigations is the possibility to use the presence of exRNAs for the early diagnosis of cancer. In collaboration with clinical partners, we work on the validation of novel tumour markers for the non-invasive diagnosis of bladder and breast cancer.





Miller,C.L., Haas,U., Diaz,R., Leeper,N.J., Assimes,T.L., Kaiser,F.J., Perisic,L., Hedin,U., Maegdefessel,L., Schunkert,H., Erdmann,J., Quertermous,T. & Sczakiel,G.
Coronary Heart Disease-Associated Variation in TCF21 Disrupts a miR-224 Binding Site and miRNA-Mediated Regulation.
PLoS Genet., 10, e1004263. / doi: 10.1371 (2014).

Dornseifer,S. & Sczakiel,G.
Computational identification of biologically functional non-hairpin GC-helices in human Argonaute mRNA.
BMC Bioinformatics, 14:122 (2013).

Haas U, Sczakiel G, Laufer SD.
MicroRNA-mediated regulation of gene expression is affected by disease-associated SNPs within the 3'-UTR via altered RNA structure.
RNA Biol. 2012 Jun 1;9(6). [Epub ahead of print]


Xiao Y, Ma Q, Restle T, Shang W, Svergun DI, Ponnusamy R, Sczakiel G, Hilgenfeld R.
Nonstructural proteins 7 and 8 of feline coronavirus form a 2:1 heterotrimer that exhibits primer-independent RNA polymerase activity.
J Virol. 2012 Apr;86(8):4444-54. Epub 2012 Feb 8.

Blaum BS, Wünsche W, Benie AJ, Kusov Y, Peters H, Gauss-Müller V, Peters T, Sczakiel G.

Functional binding of hexanucleotides to 3C protease of hepatitis A virus.
Nucleic Acids Res. 2012 Apr;40(7):3042-55. Epub 2011 Dec 10.

Lavergne T, Baraguey C, Dupouy C, Parey N, Wuensche W, Sczakiel G, Vasseur JJ, Debart F.
Synthesis and preliminary evaluation of pro-RNA 2'-O-masked with biolabile pivaloyloxymethyl groups in an RNA interference assay.
J Org Chem. 2011 Jul 15;76(14):5719-31. Epub 2011 Jun 16.

Mescalchin,A., Wünsche,W. & Sczakiel,G.
Specific recognition of proteins by array-bound hexanucleotides.
Angewandte Chemie Int. Ed. Engl., 50, 1052-1054 (2011).


 
Impressum
Last updated: 14.10.2016