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Refers to nucleic acid base sequences proceeding the opposite direction from expression.
upstreamIn genetics, at a stage in the sequence of processes in the expression of a gene that is further away from the final protein product. The term is also used to mean in the direction of the 5'-end of a chain of bases in DNA (see PHOSPHODIESTER BOND). In both cases the opposite sense is called ‘downstream’.
upstream(of a LOCUS on a DNA molecule) relating to a position in the opposite direction to that in which TRANSCRIPTION occurs, often before the transcription start site in DNA. By convention, the DNA sequence of genes is shown from 5′ (left) to 3′(right), so that if A is on the 5′ side of B, A is upstream of B. Compare DOWNSTREAM.
a term used in molecular biology to describe nucleotides of a nucleic acid molecule which lie in the 5′ direction from a particular reference point such as the site of initiation of transcription. See also downstream.
upstream activating site
DNA sequences that are upstream from the promoter and have a regulatory role in transcription.