i have spent some time on that angle before. interesting interactions.
Genetic evidence that the human CYP2R1 enzyme is a key vitamin D 25-hydroxylasehttp://www.ncbi.nlm.nih.gov/pmc/articles/PMC419671/
"The synthesis of bioactive vitamin D requires hydroxylation at the 1α and 25 positions by cytochrome P450 enzymes in the kidney and liver, respectively. The mitochondrial enzyme CYP27B1 catalyzes 1α-hydroxylation in the kidney
Genetic Disorders and Defects in Vitamin D Actionhttp://www.ncbi.nlm.nih.gov/pmc/articles/PMC2879401/
"The critical enzyme to synthesize calcitriol from 25(OH)D
, the circulating hormone precursor, is 25-hydroxyvitamin D-1α-hydroxylase
1,25(OH)2D response to combined zinc and phosphorus depletion in rats.
"...Zn depletion limits
the increase in plasma 1,25(OH)2D concentration
associated with P depletion. The mechanism is unknown but may involve an effect of Zn on renal 25(OH)D 1-α-hydroxylase synthetic activity
The Vitamin D Receptor: New Paradigms for the Regulation of Gene Expression by 1,25-Dihydroxyvitamin D3http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2879406/
"The actions of the vitamin D hormone 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) are mediated by the vitamin D receptor (VDR),
a ligand-activated transcription factor that functions to control gene expression... the VDR protein is comprised of three distinct regions, an N-terminal dual zinc finger DNA binding domain
, a C-terminal ligand-binding activity domain and an extensive and unstructured region that links the two functional domains of this protein together.
Effect of zinc deficiency on the protein expression of vitamin D receptor and calcium binding protein in growth-stage rats duodenal mucosahttp://www.ncbi.nlm.nih.gov/pubmed/16623997
"Immunohistochemistry demonstrated that the intestinal mucosal expression of both VDR protein and CaBP protein in ZD rats significantly decreased
."Zinc-induced conformational changes in the DNA-binding domain of the vitamin D receptor
determined by electrospray ionization mass spectrometry
"...the binding of the first Zn2+ ion to the protein results in very little conformational change in the protein. The binding of a second Zn2+ ion resulted in a significant alteration in the structure of the protein as indicated by changes in both the multiply charged ESI and far-UV CD spectra."
Zinc increases the activity of vitamin D-dependent promoters in osteoblasts.http://www.ncbi.nlm.nih.gov/pubmed/10777672
To determine whether zinc alters 1alpha,25-dihydroxyvitamin D(3)-regulated genes in cells, we permanently transfected rat osteoblasts with two vitamin D-dependent promoter-reporter systems and examined their responses to 1alpha,25-dihydroxyvitamin D(3) in the presence of increasing amounts of extracellular zinc. When extracellular zinc concentrations were increased in the presence of 1alpha,25-dihydroxyvitamin D(3), there was an increase in the activity of 1alpha,25-dihydroxyvitamin D(3)-dependent promoters with increasing concentrations of zinc. The effect was specific for zinc
since metals such as copper failed to increase the activity of 1alpha,25-dihydroxyvitamin D(3)-dependent promoters."
Zinc deficiency, DNA damage and cancer riskhttp://www.sciencedirect.com/science/ar ... 6304001408
"Zinc plays a critical role in the regulation of transcription and replication of DNA through zinc finger proteins. Additionally, many DNA repair mechanisms involve zinc. Many proteins involved in both base and nucleotide excision repairs are zinc finger or zinc-associated proteins"