Identification of unique interactions between the flexible linker and the RecA-like domains of DEAD-box helicase Mss116
| Autor: | Jung-Chi Liao, Yuan Zhang, Mirko Palla, Andrew Y. Sun |
|---|---|
| Rok vydání: | 2013 |
| Předmět: |
Saccharomyces cerevisiae Proteins
Sequence analysis RNA Splicing Molecular Sequence Data Computational biology Saccharomyces cerevisiae Molecular Dynamics Simulation Ligands DEAD-box RNA Helicases Protein structure General Materials Science Amino Acid Sequence Peptide sequence biology Sequence Homology Amino Acid Chemistry RNA Helicase Group II intron Condensed Matter Physics Molecular biology Protein Structure Tertiary Rec A Recombinases Cross-Linking Reagents RNA splicing Mutation biology.protein Linker |
| Zdroj: | Journal of physics. Condensed matter : an Institute of Physics journal. 25(37) |
| ISSN: | 1361-648X |
| Popis: | DEAD-box RNA helicases are ATP-dependent proteins implicated in nearly all aspects of RNA metabolism. The yeast DEAD-box helicase Mss116 is unique in its functions of splicing group I and group II introns and activating mRNA translation, but the structural understanding of why it performs these unique functions remains unclear. Here we used sequence analysis and molecular dynamics simulation to identify residues in the flexible linker specific for yeast Mss116, potentially associated with its unique functions. We first identified residues that are 100% conserved in Mss116 of different species of the Saccharomycetaceae family. The amino acids of these conserved residues were then compared with the amino acids of the corresponding residue positions of other RNA helicases to identify residues that have distinct amino acids from other DEAD-box proteins. Four residues in the flexible linker, i.e. N334, E335, P336 and H339, are conserved and Mss116-specific. Molecular dynamics simulation was conducted for the wild-type Mss116 structure and mutant models to examine mutational effects of the linker on the conformational equilibrium. Relatively short MD simulation runs (within 20 ns) were enough for us to observe mutational effects, suggesting serious structural perturbations by these mutations. The mutation of E335 depletes the interactions between E335 and K95 in domain 1. The interactions between N334/P336 and N496/I497 of domain 2 are also abolished by mutation. Our results suggest that tight interactions between the Mss116-specific flexible linker and the two RecA-like domains may be mechanically required to crimp RNA for the unique RNA processes of yeast Mss116. |
| Databáze: | OpenAIRE |
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