Gene Association: TLCD3B
UniProt Search:
TLCD3B (PROTEIN_CODING)
Function Description: TLC domain containing 3B
found 3 associated metabolites with current gene based on the text mining result from the pubmed database.
24,25-Dihydroxyvitamin D
24,25-Dihydroxyvitamin D (24R,25(OH)2D3) circulates in blood at concentrations about 1000 times higher than 1alpha,25(OH)2D3. 24-Hydroxylase is present in the proximal convoluted tubule cells of the kidney and in virtual all target cells of 1alpha,25(OH)2D3. Interestingly, 1alpha,25(OH)2D3 is a very strong inducer of 24-hydroxylase activity and 24R,25(OH)2D3 formation. Also parathyroid hormone (PTH) regulates 24-hydroxylase activity but in a tissue specific manner, i.e. inhibitory in the kidney while a synergistic effect together with 1alpha,25(OH)2D3 is observed in osteoblasts. Generally, 24-hydroxylation has been considered the first step in the degradation pathway of 1alpha,25(OH)2D3 and 25-(OH)D3. However, through the past decades data have accumulated that 24R,25(OH)2D3 is not merely a degradation product but has effects on its own. Classic studies have demonstrated the significance of 24R,25(OH)2D3 for normal chicken egg hatchability and calcium and phosphorus homeostasis. More recently it became apparent that 24R,25(OH)2D3 also has distinct effects on cartilage in particular the resting zone cells. 24R,25(OH)2D3 stimulates osteocalcin synthesis in human osteoblasts. 24R,25(OH)2D3 plays a role in bone metabolism but that it acts in concert with 1alpha,25(OH)2D3 to obtain an optimal effect. (PMID: 11179746). D018977 - Micronutrients > D014815 - Vitamins > D004100 - Dihydroxycholecalciferols D018977 - Micronutrients > D014815 - Vitamins > D006887 - Hydroxycholecalciferols D000077264 - Calcium-Regulating Hormones and Agents D050071 - Bone Density Conservation Agents
24R,25-Dihydroxyvitamin D3
24R,25-Dihydroxyvitamin D3, also known as 24(R),25(OH)2D3, is a vitamin D metabolite; a dihydroxylated form of the seco-steroid. With the identification of a target cell, the growth plate resting zone (RC) chondrocyte, studies indicate that there are specific membrane-associated signal transduction pathways that mediate both rapid, nongenomic, and genomic responses of RC cells to 24(R),25(OH)2D3. These studies indicate that 24(R),25(OH)2D3 plays an important role in endochondral ossification by regulating less mature chondrocytes and promoting their maturation in the endochondral lineage. 24(R),25(OH)2D3 binds RC chondrocyte membranes with high specificity, increasing protein kinase C (PKC) activity. The effect is stereospecific; 24R,25(OH)2D3, but not 24S,25(OH)2D3, causes the increase, indicating a receptor-mediated response. Phospholipase D-2 (PLD2) activity is increased, resulting in increased production of diacylglycerol (DAG), which in turn activates PKC. 24(R),25(OH)2D3 does not cause translocation of PKC to the plasma membrane but activates existing PKCα. There is a rapid decrease in Ca2+ efflux, and the influx is stimulated. 24(R),25(OH)2D3 also reduces arachidonic acid release by decreasing phospholipase A2 (PLA2) activity, thereby decreasing the available substrate for prostaglandin production via the action of cyclooxygenase-1. PGE2 that is produced acts on the EP1 and EP2 receptors expressed by RC cells to downregulate PKC via protein kinase A, but the reduction in PGE2 decreases this negative feedback mechanism. Both pathways converge on MAP kinase, leading to new gene expression. One consequence of this is the production of new matrix vesicles containing PKCα and PKCγ, and an increase in PKC activity. The chondrocytes also produce 24(R),25(OH)2D3, and the secreted metabolite acts directly on the matrix vesicle membrane. Only PKCγ is directly affected by 24(R),25(OH)2D3 in the matrix vesicles, and activity of this isoform is inhibited. This effect may be involved in the control of matrix maturation and turnover. 24(R),25(OH)2D3 causes RC cells to mature along the endochondral developmental pathway, where they become responsive to 1α,25(OH)2D3 and lose responsiveness to 24(R),25(OH)2D3, a characteristic of more mature growth zone (GC) chondrocytes. 1α,25(OH)2D3 elicits its effects on GC through different signal transduction pathways than those used by 24(R),25(OH)2D3 (PMID: 11179745). 24R,25-Dihydroxyvitamin D3 (24(R),25(OH)2D3 ) is a vitamin D metabolite, a dihydroxylated form of the seco-steroid. With the identification of a target cell, the growth plate resting zone (RC) chondrocyte, studies indicate that there are specific membrane-associated signal transduction pathways that mediate both rapid, nongenomic and genomic responses of RC cells to 24(R),25(OH)2D3. These studies indicate that 24(R),25(OH)2D3 plays an important role in endochondral ossification by regulating less mature chondrocytes and promoting their maturation in the endochondral lineage. D018977 - Micronutrients > D014815 - Vitamins > D004100 - Dihydroxycholecalciferols D018977 - Micronutrients > D014815 - Vitamins > D006887 - Hydroxycholecalciferols D000077264 - Calcium-Regulating Hormones and Agents D050071 - Bone Density Conservation Agents
Secalciferol
D018977 - Micronutrients > D014815 - Vitamins > D004100 - Dihydroxycholecalciferols D018977 - Micronutrients > D014815 - Vitamins > D006887 - Hydroxycholecalciferols D000077264 - Calcium-Regulating Hormones and Agents D050071 - Bone Density Conservation Agents
