Benutzer:Hoffmeier/Frame

Als Leserahmen (engl. reading frame) oder Leseraster wird eine kontinuierliche Abfolge (Sequenz) von Codons (Nukleobasen-Triplets) auf der DNA oder RNA bezeichnet. Es gibt drei mögliche Leserahmen auf dem mRNA-Strang und sechs bei der doppelsträngigen DNA.

In biology, a reading frame is a contiguous and non-overlapping set of three-nucleotide codons in DNA or RNA. There are 3 possible reading frames in a mRNA strand and six in a double stranded DNA molecule due to the two strands from which transcription is possible. This leads to the possibility of overlapping genes and there may be many of these in bacteria. Some viruses e.g. HBV and BYDV use several overlapping genes in different reading frames.

In rare cases a translating ribosome may shift from one frame to another, a translational frameshift. It is distinct from a frameshift mutation as the nucleotide sequence (DNA or RNA) is not altered only the frame in which it is read.

Ein Leserahmen, der ein Startcodon und Stoppcodon enthält, wird als offener Leserahmen (ORF) bezeichnet.

  5'                                                   3' 
  atgcccaagctgaatagcgtagaggggttttcatcatttgaggacgatgtataa 

1 atg ccc aag ctg aat agc gta gag ggg ttt tca tca ttt gag gac gat gta taa 
   M   P   K   L   N   S   V   E   G   F   S   S   F   E   D   D   V   *  
2  tgc cca agc tga ata gcg tag agg ggt ttt cat cat ttg agg acg atg tat 
    C   P   S   *   I   A   *   R   G   F   H   H   L   R   T   M   Y  
3   gcc caa gct gaa tag cgt aga ggg gtt ttc atc att tga gga cga tgt ata 
     A   Q   A   E   *   R   R   G   V   F   I   I   *   G   R   C   I

5'-...TACACACGAATAAAAGATAACAAAGATGAGTAAAGGAGAAGAACTTTTCACTGGAGTTGT...-3'

5'-...TACACACGAATAAAAGATAACAAAGATGAGTAAAGGAGAAGAACTTTTCACTGGAGTTGT...-3'
3'-...ACAACTCCAGTGAAAAGTTCTTCTCCTTTACTCATCTTTGTTATCTTTTATTCGTGTGTA...-5'

        H  T  N  K  R  *  Q  R  *  V  K  E  K  N  F  S  L  E  L
        CACACGAATAAAAGATAACAAAGATGAGTAAAGGAGAAGAACTTTTCACTGGAGTTGT
       T  H  E  *  K  I  T  K  M  S  K  G  E  E  L  F  T  G  V
       ACACACGAATAAAAGATAACAAAGATGAGTAAAGGAGAAGAACTTTTCACTGGAGTTGT
      Y  T  R  I  K  D  N  K  D  E  *  R  R  R  T  F  H  W  S  C 
      TACACACGAATAAAAGATAACAAAGATGAGTAAAGGAGAAGAACTTTTCACTGGAGTTGT

        5'-...TACACACGAATAAAAGATAACAAAGATGAGTAAAGGAGAAGAACTTTTCACTGGAGTTGT...-3'

1.Raster:     TACACACGAATAAAAGATAACAAAGATGAGTAAAGGAGAAGAACTTTTCACTGGAGTTGT
Translation:  Y  T  R  I  K  D  N  K  D  E  *  R  R  R  T  F  H  W  S  C 

2.Raster:     -ACACACGAATAAAAGATAACAAAGATGAGTAAAGGAGAAGAACTTTTCACTGGAGTTGT
Translation:   T  H  E  *  K  I  T  K  M  S  K  G  E  E  L  F  T  G  V  

3.Raster:     --CACACGAATAAAAGATAACAAAGATGAGTAAAGGAGAAGAACTTTTCACTGGAGTTGT
Translation:    H  T  N  K  R  *  Q  R  *  V  K  E  K  N  F  S  L  E  L

3'-...ATGTGTGCTTATTTTCTATTGTTTCTACTCATTTCCTCTTCTTGAAAAGTGACCTCAACA