Hello, I am trying to wrap my head around anti-sense transcripts.
When looking at refseq's annotations on IGV you can see a (-) or a (+) for each transcript.
From reading this paper https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3664467/#sec-2title I understand that transcription from the antisense strand is most common and primarily comprises protein coding genes. However, it mentions there can be transcription from the sense strand? Referring to the image below and what I think I know about RNA polymerase is that it only acts on the antisense (-) strand because it builds from 5' -> 3'.
So how can it be the case that there can be sense (+) or antisense (-) transcripts if RNA polymerase builds in one direction? I understand the from this image you could simultaneously transcribe from the other strand, but then the naming scheme would flip, no? Then they would both be considered (-) right?