Talk:Reading frame

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Vague statement

"Double stranded DNA has six different reading frames molecule due to the two strands from which transcription is possible - three of them reading forward and three of them reading backwards." Is it correct to interpret this statement as saying: double stranded dna consists of 2 strands with opposite alignment (3' 5' direction is reversed, and reading frame may be on either side, but is always read in the same 3' to 5' or was it opposite direction)? otherwise I see 2(strands)*3(nucleotides)*2directions=12 reading frames... — Preceding unsigned comment added by 213.49.90.22 (talk) 06:04, 27 November 2011 (UTC)[reply]

  • Double stranded DNA consists of two strands with opposite alignment (i.e., the strands are antiparallel). Transcription (I think, this could be wrong) only happens in a 3' to 5' direction, or to put it another way, from the hydroxyl end of a DNA strand towards its phosphoryl end. Therefore each DNA strand can only have three possible reading frames (being read in one direction), and therefore double stranded DNA has a total of six reading frames. To make things more confusing, I think that RNA may be able to be read in either direction during translation, I will check this later, and try to remove ambiguity from the article -Zynwyx (talk) 09:57, 29 May 2012 (UTC)[reply]
The use of "3' to 5' direction" without any prior explanation has to be corrected. What does it mean? Where is this terminology taken from? How is the reader supposed to know? LeadSongDog come howl! 00:58, 20 June 2012 (UTC)[reply]
I have added a short section in the lede explaining directionality of nucleic acid strands, but it might still be too technical. Also sorry, I think I may have rearranged a couple of your references to the wrong place, please feel free to move them back. I've added that a DNA double helix (technically) has 12 reading frames, but not all of them are biologically relevant. I think this page may need attention from an expert, I am not sure what the consensus is on what counts as a reading frame or not, so am reluctant to make any more edits. Does a reading frame need to be biologically relevant to be counted as such? -Zynwyx (talk) 01:40, 21 June 2012 (UTC)[reply]
A double helix only has 6 possible reading frames, as each strand can only be read in one direction. If you're going the other direction, you're reading the other strand. Note that stop codons have no relevance during transcription: in the case of mRNAs, transcription is terminated some distance after the stop codon by a separate nucleic acid sequence, whereas non-coding RNAs don't have stop codons at all.
What this and related articles really need is some good, clear diagrams. We could also replace the early refs to papers with refs to a free textbook such as Alberts Molecular Biology of the Cell. 4th ed, available here, which is less technical and better illustrated.
Adrian J. Hunter(talkcontribs) 11:06, 21 June 2012 (UTC)[reply]
This glossary helped. The missing nugget was in the Directionality (molecular biology) article, though still not terribly clear there. The "5 prime end" and "3 prime end" are distinguished by where the phosphoryl or hydroxyl attachments to them are made. The number "5" refers to "which" carbon (the fifth) in the furanose sugar-ring at that head end is phosphorylated or hydroxylated, just as the number "3" refers to the third carbon in the sugar ring at the tail end is hydroxylated or phosphorylated. These carbon positions on the ring are counted from "1" (where the basic group attaches). I hope that's now clarified after my last edit, though it probably still needs more elaboration. LeadSongDog come howl! 18:05, 21 June 2012 (UTC)[reply]

Question

According to Lewin's Genes XI, the reading frame should on the mRNA rather than on the DNA. the DNA needn't be divided into the triplets, because the molecule translated is the mRNA rather than DNA.And the enzyme just transcrips the DNA, not divide it. The dividing happens when the ribosome is reading the mRNA. -- パンツァー VI-II Fu7ラジオ❂In the Republic of China 103rd.民國103年 14:24, 13 November 2015 (UTC)[reply]

Assessment comment

The comment(s) below were originally left at Talk:Reading frame/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.

Rated "high" as high school/SAT biology content, part of genetic code and gene expression. - tameeria 00:38, 19 February 2007 (UTC)[reply]

Last edited at 00:38, 19 February 2007 (UTC). Substituted at 04:00, 30 April 2016 (UTC)

1 accagacgct gacagctact cagaatcaaa tctggttcca tccagagaca agcgaagaca

      61 agagaagcag agcgagcggc gcgttcccga tcctcggcca ggaccagcct tccccagagc
     121 atccacgccg cggagcgcaa ccttcccagg agcatccctg ccgcggagcg caactttccc
     181 cggagcatcc acgccgcgga gcgcagcctt ccagaagcag agcgcggcgc catggccaag
     241 aacacggcga tcggcatcga cctgggcacc acctactcgt gcgtgggcgt gttccagcac
     301 ggcaaggtgg agatcatcgc caacgaccag ggcaaccgca cgacccccag ctacgtggcc
     361 ttcaccgaca ccgagcgcct catcggggac gccgccaaga accaggtggc gctgaacccg
     421 cagaacaccg tgttcgacgc gaagcggctg atcggccgca agttcggcga tgcggtggtg
     481 cagtccgaca tgaagcactg gcccttccag gtggtgaacg acggcgacaa gcccaaggtg
     541 caggtgaact acaagggcga gagccggtcg ttcttcccgg aggagatctc gtccatggtg
     601 ctgacgaaga tgaaggagat cgctgaggcg tacctgggcc acccggtgac caacgcggtg
     661 atcacggtgc ccgcctactt caacgactct cagcggcagg ccaccaagga cgcgggcgtg
     721 atcgccggtc taaacgtgct gcggatcatc aacgagccca cggcggccgc catcgcctac
     781 gggctggacc ggaccggcaa gggcgagcgc aacgtgctca tcttcgacct ggggggcggc
     841 acgttcgacg tgtccatcct gacgatcgac gacggcatct tcgaggtgaa ggccacggcg
     901 ggcgacacgc acctgggagg ggaggacttc gacaaccggc tggtgagcca cttcgtggag
     961 gagttcaaga ggaagcacaa gaaggacatc agccagaaca agcgcgcggt gcggcggctg
    1021 cgcacggcgt gtgagagggc caagaggacg ctgtcgtcca gcacccaggc cagcctggag
    1081 atcgactctc tgttcgaggg catcgacttc tacacatcca tcacgcgggc gcggttcgaa
    1141 gagctgtgct cggacctgtt ccgcggcacg ctggagcccg tggagaaggc cctgcgcgac
    1201 gccaagatgg acaaggcgca gatccacgac ctggtgctgg tgggcggctc gacgcgcatc
    1261 cccaaggtgc agaagctgct gcaggacttc ttcaacgggc gcgacctgaa caagagcatc
    1321 aacccggacg aggcggtggc ctacggggcg gcggtgcagg cggccatcct gatgggggac
    1381 aagtcggaga acgtgcagga cctgctgctg ctggacgtgg cgccgctgtc gctgggcctg
    1441 gagactgcgg gcggcgtgat gacggcgctc atcaagcgca actccaccat ccccaccaag
    1501 cagacgcaga ccttcaccac ctactcggac aaccagcccg gggtgctgat ccaggtgtac
    1561 gagggcgaga gggccatgac gcgcgacaac aacctgctgg ggcgcttcga gctgagcggc
    1621 atcccgccgg cgcccagggg cgtgccgcag atcgaggtga ccttcgacat cgacgccaac
    1681 ggcatcctga acgtcacggc caccgacaag agcaccggca aggccaacaa gatcaccatc
    1741 accaacgaca agggccgcct gagcaaggag gagatcgagc gcatggtgca ggaggccgag
    1801 cgctacaagg ccgaggacga ggtgcagcgc gacagggtgg ccgccaagaa cgcgctcgag
    1861 tcctatgcct tcaacatgaa gagcgccgtg gaggacgagg gtctcaaggg caagctcagc
    1921 gaggctgaca agaagaaggt gctggacaag tgccaggagg tcatctcctg gctggactcc
    1981 aacacgctgg ccgacaagga ggagttcgtg cacaagcggg aggagctgga gcgggtgtgc
    2041 agccccatca tcagtgggct gtaccagggt gcgggtgctc ctggggctgg gggcttcggg
    2101 gcccaggcgc cgccgaaagg agcctctggc tcaggaccca ccatcgagga ggtggattag
    2161 aggcctctgc tggctctccc ggtgtggtct agaaaacaga ctctttgcac ttgatagctg
    2221 cttgggcacc gattactgtc aaggttattt aaagtcttct tcatggttca gtttaaagtt
    2281 acagtctttc ttaaggtaat tgcgttgact gttaaatttt gtatgcatat atatatatat
    2341 atatatatat atatatatat attcaaatat attcaaagta atgttgggag cagcactgtg
    2401 cactgtacca ggggattatg ttttatagct aatgatgtgt aaagtctaaa gatttttttg
    2461 taatttttat atcagtgttc cagtagcctg ggaagacata tagtctagct gcccagttcc
    2521 ctggagatgg tcatctctaa gacaaagtgt cttaaacaaa cgtcttggca ctgtgtacta
    2581 cataacttta ctcttttgta cttaaaactt tatctgcttg tccatgttaa ggttttgtgg
    2641 tataaccagt atgttctttg catttaatct aagtaggtta aagatggtgt atccttcctg
    2701 catacatgtc tacactgcca ccctgtgtac atttttttct ttgcatcact acaaactaat
    2761 gaaaaaaact tttatgactt aaatattcaa aataaaaggt tacaagtata

// — Preceding unsigned comment added by 113.250.155.246 (talk) 14:19, 3 June 2017 (UTC)[reply]