reading frame(redirected from open reading frame (ORF))
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read·ing frame(rēd'ing frām),
The grouping of nucleotides by threes into codons. See: frameshift mutation.
One of the three possible ways in which an mRNA sequence of nucleotides can be read as a series of base triplets to specify the amino acids in a protein chain.
reading frameAn imaginary window through which base pairs can be inspected three at a time, and which provides a way in which a nucleotide sequence can be viewed as three different sets of CODONs only one of which is correct.
the actual codons that are translated (read) during mRNA synthesis. In principle a DNA sequence can be transcribed in any one of three different reading frames, each of which will specify a completely different polypeptide. Usually only one of the three reading frames is transcribed.
open reading frame (ORF)
an extended sequence in mRNA that is free of stop codons.