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 See https://en.wikipedia.org/wiki/Inflammatory_cytokine Assumed to be Phospholipase C Plasma membrane Ca2+-ATPases (PMCAs) a06 c03 altered calcium/calcium-mediated signaling pathway PW:0001169 Pathway Ontology 30190470 PubMed Structure of the human plasma membrane Ca(2+)-ATPase 1 in complex with its obligatory subunit neuroplastin. Nat Commun 2018 Gong D Chi X Ren K Huang G Zhou G Yan N Lei J Zhou Q 31867158 PubMed Role of vitamin D receptor in the regulation of CYP3A gene expression Acta Pharmaceutica Sinica B 2019 Xuan Qin Xin Wang neuron CL:0000540 Cell Type hepatocyte CL:0000182 Cell Type epidermal cell CL:0000362 Cell Type 28202503 PubMed Vitamin D and Depression: Cellular and Regulatory Mechanisms. Pharmacol Rev 2017 Berridge MJ mental depression DOID:1596 Disease