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.
1 The purpose of the promoter is to bind transcription factors that control the initiation of transcription.  The promoter region can be short or quite long; the longer the promoter is, the more available space for proteins to bind.