experimental evidence expression pattern evidence eco Use this evidence type when the annotation is inferred from the timing or location of expression of a gene. It may be difficult to determine whether the expression pattern truly indicates that a gene plays a role in a given process. The 10 previously identified GlnR-regulated genes were all confirmed to be under GlnR control during nitrogen stress (i.e. differential expression in the wild type compared to the DeltaglnR mutant), but in addition a total of 392 genes were significantly up-regulated and 291 significantly down regulated (Additional file 1: Table S1). This indicates that GlnR mediates (directly or indirectly) the expression of over 680 genes. ECO:0000008 A type of experimental evidence that is based on characterization of gene expression.