α transducin is present in blue-, green-, and red-sensitive cone photoreceptors in the human retina

doi:10.1016/0896-6273(89)90261-4

Neuron

Volume 3, Issue 3, September 1989, Pages 367-376

https://doi.org/10.1016/0896-6273(89)90261-4 Get rights and content

Abstract

Phototransduction in vertebrate rod and cone photoreceptor cells involves G protein-mediated light stimulation of cGMP hydrolysis. Enzymes of the cGMP hydrolysis cascades of rods and cones are products of different genes. Three different classes of cones in the human retina are maximally sensitive to either blue, green, or red light. Distinct opsin genes are expressed in each type of cone. The distribution of cone types in human retina was determined using anti-peptide antibodies that recognize specific amino acid sequences in green/red opsin and blue opsin. These antibodies together with an anti-peptide antibody against T_cα were used in double labeling experiments to demonstrate the presence of the T_cα peptide in all types of cones. cDNA clones corresponding to human rod and cone transducin α subunit (T_cα and T_cα) genes were isolated. Southern blot analyses of human genomic DNA suggest that there is only one rod T_α gene but more than one cone T_α gene. The multiple T_cα genes could be closely related genes or different T_cα alleles, or one could be a pseudogene.

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Neuron

Articleα transducin is present in blue-, green-, and red-sensitive cone photoreceptors in the human retina

Abstract

Vision Res.

Anal. Biochem.

J. Biol. Chem.

Anal. Biochem.

J. Biol. Chem.

J. Biol. Chem.

J. Biol. Chem.

Anal. Biochem.

FEBS Lett.

FEBS Lett.

Vis. Res.

J. Biol. Chem.

FEBS Lett.

Identification of a subtype of cone photoreceptor, likely to be blue sensitive, in the human retina

J. Comp. Neurol.

Photoreceptor signals and vision

Invest. Ophthalmol. Vis. Sci.

Laboratory methods: a method for isolation of intact, translationally active ribonucleic acid

DNA

Cyclic GMP increases photocurrent and light sensitivity of retinal cones

Nature

Identification, purification, and functional reconstitution of the cCMP-dependent channel from rod photoreceptors

Human visual pigments: microspectrophotometric results from the eyes of seven persons

Density profile of blue sensitive cones along the horizontal meridian of macaque retina

Invest. Ophthal. Vis. Sci.

cGMP phosphodiesterase of retinal rods is regulated by two inhibitory subunits

Repetitive segmental structure of the transducin β subunit: homology with the yeast CDC4 gene and identification of related mRNA

Distinct forms of the β subunit of GTP-binding regulatory proteins identified by molecular cloning

Article
α transducin is present in blue-, green-, and red-sensitive cone photoreceptors in the human retina