Ribonucleoproteins are complexes consisting of proteins and RNA. One of the most prominent examples of a such system is the ribosome, composed of several RNAs and different protein units and plays an essential role in gene expression. Ribonucleoproteins mostly form very complex structures that take very specific, essential tasks in the cell. To understand the function of these complexes the knowledge of the structure plays a crucial role. The research in this field is highly relevant and has a huge significance in medical studies.
Small nucleolar RNA complexes (snoRNA)
SnoRNAs are non-coding nucleic acids used in the modification of other functional RNA, RNA processing or genetic imprinting. In general, we can differentiate between two types of snoRNA: box H/ACA and box C/D. box H/ACA and box C/D snoRNAs form complexes with several proteins, which allow specific recognition of the target structures. The C/D snoRNA serves as a guide-RNA for the 2’-O-methylation of the ribose, whereas the H/ACA snoRNA is the guide-RNA for rRNA and snRNA during the pseudouridylation.
The box C/D is a complex of two snoRNAs that serve as a complex framework and several proteins (see Figure). The two snoRNAs have complementary base sequences and form base pairs at two different positions called C and D. The box C/D is used for the methylation of guide RNA, which is needed as protection against degradation or modification of catalytically functional RNA molecules. The malfunction of the box C/D, caused by for example mutation is associated with many diseases, such as diabetes or Prader Willie syndrome, which is caused by a gene mutation in chromosome 15.
In cooperation with university Hannover (Alexander Marchanka) our group investigates the possible application of DNP in such complexes. Here, especially the method of SCREAM-DNP seems to be promising.