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Why the sense strand is only involved in transcription though the antisense strand just has the compliment strand of the sense strand?

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    $\begingroup$ I don't understand your question. The sense (coding) and antisense (template) strands are defined by which strand is transcribed. $\endgroup$ – canadianer Jul 9 '15 at 18:34
  • $\begingroup$ Is there anything that always a particular strand is transcribed $\endgroup$ – Naveen Kumaar Jul 9 '15 at 18:36
  • $\begingroup$ I mean when the sense strand is being transcribed for one gene why can't the antisense strand can be transcribed simultaneously for another gene as both strands contain the same genetic material $\endgroup$ – Naveen Kumaar Jul 9 '15 at 18:38
  • $\begingroup$ Which strand is transcribed depends on the gene. The terms sense and antisense are only useful when talking about a single gene. Between genes on a chromosome, a DNA strand may be sense for one gene and antisense for another. $\endgroup$ – canadianer Jul 9 '15 at 18:41
  • $\begingroup$ This paper presents an interesting idea that the 2 classes of amino acyl tRNA synthetases originated as 2 genes on opposite strands of a double-stranded RNA. This would be helpful in a primitive mostly-RNA world where making long RNAs would have been hard and overlapping the genes would save space. $\endgroup$ – user137 Jul 9 '15 at 21:14
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The short answer is the transcription machinery will only bind on the correct orientation. The binding of proteins and such to the promoter DNA strand is determined by the sequence of the DNA, the sequence is not correct on the anti-sense strand for a given gene.

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One of the reasons why DNA is double stranded--this means DNA has sense and antisense strands--is to make a copy.

During transcription, RNAs are transcribed referring to anti-sense strand sequences--making base pairs with anti-sense strand. In other words, the sense strand does not do anything during transcription.

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Either strand of DNA can be sense or antisense. SWBarnes2 posts that the "transcription machinery will only bind on the correct orientation" and that is indeed what determines which strand is sense. But note his important statement "the sequence is not correct on the anti-sense strand FOR A GIVEN GENE" (my emphasis). As you move from gene to gene, the sense strand can swap strands. Coding sequences can overlap running in opposite directions, making both strands sense; this is more commonly a viral trick. Sense and antisense are defined by what sequence is found in RNA and so the map of sense and antisense strands on DNA is complicated. As you move along a strand of DNA one strand might be sense, then the other, then both, then neither.

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