Search results
Results From The WOW.Com Content Network
Retinoic acid (simplified nomenclature for all-trans-retinoic acid) is a metabolite of vitamin A 1 (all-trans-retinol) that is required for embryonic development, male fertility, regulation of bone growth and immune function. [2] All-trans-retinoic acid is required for chordate animal development, which includes all higher animals from fish to ...
During development, retinoic acid, a metabolite of vitamin A, is used to stimulate the growth of the posterior end of the organism. [12] Retinoic acid binds to retinoic acid receptors that acts as transcription factors to regulate the expression of Hox genes. Exposure of embryos to exogenous retinoids especially in the first trimester results ...
This endoplasmic reticulum protein acts on retinoids, including all-trans-retinoic acid (RA), with both 4-hydroxylation and 18-hydroxylation activities. This enzyme regulates the cellular level of retinoic acid which is involved in regulation of gene expression in both embryonic and adult tissues.
As for the risks of too much RA during embryogenesis, the prescription drugs tretinoin (all-trans-retinoic acid) and isotretinoin (13-cis-retinoic acid), used orally or topically for acne treatment, are labeled with boxed warnings for pregnant women or women who may become pregnant, as they are known human teratogens. [31] [32]
At 8–12 weeks of gestation, liver is a relatively bigger organ which forms 4-5-5.5% of the total body weight and protrudes through the abdominal wall. By 13 to 32 weeks of gestation, it forms 3.4% to 4.0% of the total body weight. [23] The liver weight hence forms a more or less constant proportion of the total body weight of the fetus. [24]
The hindbrain, for example, is patterned by Hox genes, which are expressed in overlapping domains along the anteroposterior axis under the control of retinoic acid. The 3 ′ (3 prime end) genes in the Hox cluster are induced by retinoic acid in the hindbrain, whereas the 5 ′ (5 prime end) Hox genes are not induced by retinoic acid and are ...
CRBP I/II, cellular-binding proteins involved in transport of retinol and metabolites into retinyl esters for storage or into retinoic acid. [14] CRABPs, cellular retinoic acid–binding proteins capable of binding retinol and retinoic acid with high affinity. [15] [16] [17] It has also been characterized that CRABPs are involved in many ...
Retinoic acid via the retinoic acid receptor influences the process of cell differentiation and, hence, the growth and development of embryos. During development, there is a concentration gradient of retinoic acid along the anterior-posterior (head-tail) axis. Cells in the embryo respond to retinoic acid differently depending on the amount present.