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Need Help to explain a possible shared promoter - (Oct/29/2005 )

I recently observed two adjancent genes use the same 5' untranslated sequence. (I am not talking about alternative splicing in one gene). I could not find any report about this biological phenomenon but I should be very careful to claim the finding. because I am new in the field of gene regulatiuon and transcription. therefore it is likely I neglected something. I would be appreicaited if someone can give me some info on this.


Are the two genes located head to head? I know BRCA1 shares a bidirectional promoter with NBR2 (see the picture below)

Attached Image

Here are two relevant references:


I seem to recall that several viral genomes are so packed with genetic info that both strands coding for two differents transcripts is commonplace.
Both if you mean the same part of one strand being used in two different and otherwise unrelated RNA transcripts, I do not know of any example.


You talked prokaryote or eukaryote here? You need to think about how translation works in this case. For eukaryotes, an IRES element can be utilized to translate a bicistronic message or a ribosome can miss a start codon without a good kozak sequence. Other than that there needs to be other "trickery" (halloween reference!) involved in this process.


Thanks for all replies. In my case the two genes are in head to tail configuration. Besides the shared the promoter the two genes have their own promoters. I am trying to figure out the biological significance of the gene organization. Any comment would be appreciated.


What about trans-splicing? Some spliced leader (SL) RNA will add to the 5' end of mRNA, this is common in Trypanosoma brucei.