CREB1 and depressive disorder: For example, Pingping et al. (2022) found that the expression of nuclear receptor subfamily 6, group A, member 1 (NR6A1) significantly increased in the hippocampus of chronic unpredictable stress (CUS)-induced mice and over-expression of NR6A1 contributed to the occurrence of depression-like behaviors and a significant reduction in the levels of phospho-CREB in normal mice.