Filler in textured paint works like spackling compound to fill the cracks, and dark, flat paint absorbs light to help conceal remaining blemishes. Be aware that dark colors will make your ceiling appear lower, so consider using very dark colors only in normally proportioned or narrow rooms.
In genetics, a promoter is a region of DNA that initiates transcription of a particular gene.
Next to the gene is the promoter. You may know the promoter already as the region where RNA polymerase binds to initiate transcription. Not all promoters have the same DNA sequence, even though RNA polymerase binds at all promoters.