Depression has been linked to (lack of) sunlight exposure and raised intracellular calcium levels. In this pathway, the role of the vitamin D pathway in calcium signaling in depression is shown. Active 1,25-dihydroxy-vitamin D3 is formed from 7-dehydrocholesterol by multiple conversion steps. It associates with RXR and VDR in the nucleus, which stimulates transcription of VDR target genes, resulting in lower intracellular calcium levels. Less sunlight exposure results in lower 1,25-dihydroxyvitamin D3 levels and therefore higher calcium levels. ef6 Type your comment here c03 mental depression DOID:1596 Human Disease Ontology altered calcium/calcium-mediated signaling pathway PW:0001169 Pathway Ontology 28202503 PubMed Vitamin D and Depression: Cellular and Regulatory Mechanisms. Pharmacol Rev 2017 Berridge MJ 31867158 PubMed Role of vitamin D receptor in the regulation of CYP3A gene expression Acta Pharmaceutica Sinica B 2019 Xuan Qin Xin Wang