Portal de Periódicos da CAPES

The Light Response of ON Bipolar Neurons Requires Gα o

2000; Society for Neuroscience; Volume: 20; Issue: 24 Linguagem: Inglês

10.1523/jneurosci.20-24-09053.2000

1529-2401

Anuradha Dhingra, Arkady Lyubarsky, Meisheng Jiang, Edward N. Pugh, Lutz Birnbaumer, Peter Sterling, Noga Vardi,

Photoreceptor and optogenetics research

ON bipolar neurons in retina detect the glutamate released by rods and cones via metabotropic glutamate receptor 6 (mGluR6), whose cascade is unknown. The trimeric G-protein G o might mediate this cascade because it colocalizes with mGluR6. To test this, we studied the retina in mice negative for the α subunit of G o (Gα o −/−). Retinal layering, key cell types, synaptic structure, and mGluR6 expression were all normal, as was the a-wave of the electroretinogram, which represents the rod and cone photocurrents. However, the b-wave of the electroretinogram, both rod- and cone-driven components, was entirely missing. Because the b-wave represents the massed response of ON bipolar cells, its loss in the Gα o null mouse establishes that the light response of the ON bipolar cell requires G o . This represents the first function to be defined in vivo for the α subunit of the most abundant G-protein of the brain .