Canadian Medical Guide > Chemicals and Drugs > Amino Acids, Peptides, and Proteins > Proteins > Eye Proteins Terms and Definitions

Eye Proteins

Arrestins - Regulatory proteins that down-regulate phosphorylated G-protein membrane receptors, including rod and cone photoreceptors and adrenergic receptors.

Crystallins - A heterogeneous family of water-soluble structural proteins found in cells of the vertebrate lens. The presence of these proteins accounts for the transparency of the lens. The family is composed of four major groups, alpha, beta, gamma, and delta, and several minor groups, which are classed on the basis of size, charge, immunological properties, and vertebrate source. Alpha, beta, and delta crystallins occur in avian and reptilian lenses, while alpha, beta, and gamma crystallins occur in all other lenses.

Eye Proteins Medical Definitions and Terms