Changes

==Roles in the Body==

==Roles in the Body==

#'''Vision''': Vitamin A in the form of 11-cis-retinal is attached to a lysine residue in rhodopsin within the retina<ref>Conway HH, et al. Vitamin A Metabolism, Action, and Role in Skeletal Homeostasis. Endocr Rev 2013 Dec;34(6):766-797.</ref>. When light hits rhodopsin it undergoes a conformational change resulting in the generation of a nerve impulse and normal phototransduction.

#'''Vision''': Vitamin A in the form of 11-cis-retinal is attached to a lysine residue in rhodopsin within the [[Eye - Anatomy & Physiology#The Wall (retina, uvea and sclera)|retina]]<ref>Conway HH, et al. Vitamin A Metabolism, Action, and Role in Skeletal Homeostasis. Endocr Rev 2013 Dec;34(6):766-797.</ref>. When light hits rhodopsin it undergoes a conformational change resulting in the generation of a nerve impulse and normal phototransduction.

#'''Growth and Cellular Differentiation''': Retinoic acid receptors (RAR) are found in [[DNA]] gene sequences affecting normal foetal development<ref>Rhinn M and Dolle P. Retinoic acid signaling during development. Development 2012;139:843–858.</ref><ref>Mark M, et al. Function of retinoic acid receptors during embryonic development. Nucl Recept Signal 2009;7:e002. </ref>. Retinoic acid receptors also control transcription of genes that synthesise extracellular matrix proteins<ref>Barber T, et al. Vitamin A Deficiency and Alterations in the Extracellular Matrix. Nutrients 2014;6:4984-5017</ref>, differentiation of mucous-secreting epithelial cells<ref>Koo JS, et al. Restoration of the mucous phenotype by retinoic acid in retinoid-deficient human bronchial cell cultures: changes in mucin gene expression. Am J Respir Cell Mol Biol 1999;20:43-52.</ref><ref name="NRC">National Research Council (NRC). Vitamins. In Nutrient Requirements for Dogs and Cats. 2006 Washington, DC: National Academies Press p.194-200.</ref>, and cellular RBP may help stabilize RNA during gene transcription<ref>Veerland AC, et al. Transcript stabilization by the RNA-binding protein HuR is regulated by cellular retinoic acid-binding protein 2. Mol Cell Biol 2014;34:2135-2146.</ref>.

#'''Growth and Cellular Differentiation''': Retinoic acid receptors (RAR) are found in [[DNA]] gene sequences affecting normal foetal development<ref>Rhinn M and Dolle P. Retinoic acid signaling during development. Development 2012;139:843–858.</ref><ref>Mark M, et al. Function of retinoic acid receptors during embryonic development. Nucl Recept Signal 2009;7:e002. </ref>. Retinoic acid receptors also control transcription of genes that synthesise extracellular matrix proteins<ref>Barber T, et al. Vitamin A Deficiency and Alterations in the Extracellular Matrix. Nutrients 2014;6:4984-5017</ref>, differentiation of mucous-secreting epithelial cells<ref>Koo JS, et al. Restoration of the mucous phenotype by retinoic acid in retinoid-deficient human bronchial cell cultures: changes in mucin gene expression. Am J Respir Cell Mol Biol 1999;20:43-52.</ref><ref name="NRC">National Research Council (NRC). Vitamins. In Nutrient Requirements for Dogs and Cats. 2006 Washington, DC: National Academies Press p.194-200.</ref>, and cellular RBP may help stabilize RNA during gene transcription<ref>Veerland AC, et al. Transcript stabilization by the RNA-binding protein HuR is regulated by cellular retinoic acid-binding protein 2. Mol Cell Biol 2014;34:2135-2146.</ref>.

#'''Immune Function''': Retinoic acid promotes T-cell differentiation and antibody production<ref>Ross AC. Vitamin A and retinoic acid in T cell-related immunity. Am J Clin Nutr 2012;96:1166S–1172S.</ref>.

#'''Immune Function''': Retinoic acid promotes T-cell differentiation and antibody production<ref>Ross AC. Vitamin A and retinoic acid in T cell-related immunity. Am J Clin Nutr 2012;96:1166S–1172S.</ref>.