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Auflistung nach Autor:in "Prohaska, Sonja J."

1 - 3 von 3
  • Konferenzbeitrag
    Converting DNA to music: COMPOSALIGN
    (German conference on bioinformatics 2009, 2009) Ingalls, Todd; Martius, Georg; Hellmuth, Marc; Marz, Manja; Prohaska, Sonja J.
    Alignments are part of the most important data type in the field of comparative genomics. They can be abstracted to a character matrix derived from aligned sequences. A variety of biological questions forces the researcher to inspect these alignments. Our tool, called COMPOSALIGN, was developed to sonify large scale genomic data. The resulting musical composition is based on COMMON MUSIC and allows the mapping of genes to motifs and species to instruments. It enables the researcher to listen to the musical representation of the genome-wide alignment and contrasts a bioinformatician's sight-oriented work at the computer.
  • Konferenzbeitrag
    Multiple sequence alignment with user-defined constraints
    (German Conference on Bioinformatics 2004, GCB 2004, 2004) Morgenstern, Burkhard; Prohaska, Sonja J.; Werner, Nadine; Weyer-Menkhoff, Jan; Schneider, Isabelle; Subramanian, Amarendran R.; Stadler, Peter F.
    In many situations, automated multi-alignment programs are not able to correctly align families of nucleic acid or protein sequences. Distantly related sequences are generally hard to align, and sequence duplications may present additional challenges to standard alignment algorithms. In the present paper, we describe a semiautomatic approach to multiple sequence alignment. The user can specify parts of the sequences that are thought to be related to each other; our software program will use these sites as anchor points and create a multiple alignment respecting these userdefined constraints. By using functionally, structurally or evolutionarily related positions of the input sequences as anchor points, the proposed method can produce alignments that are biologically more meaningful than alignments produced by fully automated procedures. We apply our approach to genomic sequences around the Hox gene cluster. As a by-product, we obtain useful insights for the further development of alignment algorithms. The described alignment approach has been integrated into the tracker software system.
  • Konferenzbeitrag
    Quantitative comparison of genomic-wide protein domain distributions
    (German Conference on Bioinformatics 2010, 2010) Parikesit, Arli A.; Stadler, Peter F.; Prohaska, Sonja J.
    Investigations into the origins and evolution of regulatory mechanisms require quantitative estimates of the abundance and co-occurrence of functional protein domains among distantly related genomes. Currently available databases, such as the SUPERFAMILY, are not designed for quantitative comparisons since they are built upon transcript and protein annotations provided by the various different genome annotation projects. Large biases are introduced by the differences in genome annotation protocols, which strongly depend on the availability of transcript information and well-annotated closely related organisms. Here we show that the combination of de novo gene predictors and subsequent HMM-based annotation of SCOP domains in the predicted peptides leads to consistent estimates with acceptable accuracy that in particular can be utilized for systematic studies of the evolution of protein domain occurrences and co-occurrences. As an application, we considered four major classes of DNA binding domains: zink-finger, leucine-zipper, winged-helix, and HMG-box. We found that different types of DNA binding domains systematically avoid each other throughout the evolution of Eukarya. In contrast, DNA binding domains belonging to the same superfamily readily co-occur in the same protein.