I apologise for the really basic question. I've probably said this a million times now but I'm returning to this field after a long time and I keep confusing myself by mis-remembering or half-remembering things from the past and it's not helping me. It would be easier coming to the field from fresh i think. Anyhow...
As i remember it, sequence databases always store the forward strand of a DNA chromsome in the 5' to 3' direction.
A gene is read in the 3' to 5' direction and so its complementary strand in the 5' to 3' direction is the same as the mRNA transcript. So i thought if a gene was on the reverse strand of a DNA molecule then the forward strand in the 5' to 3' direction gives the sequence on the corresponding mRNA (ignoring introns for simplicity).
However I'm just looking at a gene now in ensembl and this gene is described as being on the forward strand. If you look at the forward strand it contains the exact same sequence as the gene's mRNA. So to me then, if the mRNA runs on the forward strand in the 5' to 3' direction the actual gene is on the reverse strand is it not?
Is this a convention issue that I have mis-remembered? Is a gene classed as being on the forward strand if its mRNA sequence is 'on' the forward strand.
thanks for your help