BST1 and major depressive disorder: Moreover, amygdala dysfunction in CD157 KO mice may also be related to their anxiety and depression-like behavior, because abnormalities in the amygdala might be involved in PD progression and may contribute to elicitation of non-motor symptoms such as anxiety and depression in PD (Huang et al., 2015; van Mierlo et al., 2015; Vriend et al., 2016).