Rhodopsin bleaching signals in essential night blindness
نویسندگان
چکیده
منابع مشابه
Photoreversal of Rhodopsin Bleaching
A MECHANISTIC SCHEME, SHOWING CERTAIN STEPS OF RHODOPSIN BLEACHING, PROVIDES TWO WAYS OF VIEWING THE BLEACHING PROCESS: (a) The rate of bleaching depends upon the net rate of accumulation of labile species; and (b) the number of labile molecules which accumulates in a certain period is the number which has absorbed an odd number of quanta by the end of that period. Both views, based on the phot...
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The inability of night-blind persons to see at low levels of illumination is usually attributed to a defect involving the biosynthesis of the visual pigment, rhodopsin. Accordingly, it has been assumed that the retinal rods of the congenital nyctalope are deficient in rhodopsin or its precursors. To test this hypothesis, fundus refiectometry was performed on two subjects, each having a differen...
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Congenital stationary night blindness (CSNB) is an inherited and non-progressive retinal dysfunction. Here, we present the crystal structure of CSNB-causing T94I2.61 rhodopsin in the active conformation at 2.3 Å resolution. The introduced hydrophobic side chain prolongs the lifetime of the G protein activating metarhodopsin-II state by establishing a direct van der Waals contact with K2967.43, ...
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The G90D rhodopsin mutation is known to produce congenital night blindness in humans. This mutation produces a similar condition in mice, because rods of animals heterozygous (D+) or homozygous (D+/+) for this mutation have decreased dark current and sensitivity, reduced Ca(2+), and accelerated values of tau(REC) and tau(D), similar to light-adapted wild-type (WT) rods. Our experiments indicate...
متن کاملInsights into congenital stationary night blindness based on the structure of G90D rhodopsin.
We present active-state structures of the G protein-coupled receptor (GPCRs) rhodopsin carrying the disease-causing mutation G90D. Mutations of G90 cause either retinitis pigmentosa (RP) or congenital stationary night blindness (CSNB), a milder, non-progressive form of RP. Our analysis shows that the CSNB-causing G90D mutation introduces a salt bridge with K296. The mutant thus interferes with ...
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ژورنال
عنوان ژورنال: The Journal of Physiology
سال: 1972
ISSN: 0022-3751
DOI: 10.1113/jphysiol.1972.sp009949