Evidence map›Paper›PMID 33065015›Full record

ArticleCurrent biology : CB2020

Apo-Opsin and Its Dark Constitutive Activity across Retinal Cone Subtypes.

Dong-Gen Luo, Daniel Silverman, Rikard Frederiksen, Rajan Adhikari, Li-Hui Cao, John E Oatis, Masahiro Kono, M Carter Cornwall, King-Wai Yau

Open access · bronzeAbstract read
In one paragraph

Article in Current biology : CB, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 6 papers.

0numbers the graph read from it
0cells of the map it votes in
6citing papers in PubMed
0.6field-weighted citation impact, top 34% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

6 citing papers in PubMed, 13 citations in OpenAlex.

  1. Article
  2. Visual pigments underlie the sensitivity difference between day and night vision.Proceedings of the National Academy of Sciences of the United States of America · 2025
    Article
  3. Dark continuous noise from visual pigment as a major mechanism underlying rod-cone difference in light sensitivity.Proceedings of the National Academy of Sciences of the United States of America · 2024
    Article
  4. Loss of functionaliScience · 2024
    Article
  5. Low signaling efficiency from receptor to effector in olfactory transduction: A quantified ligand-triggered GPCR pathway.Proceedings of the National Academy of Sciences of the United States of America · 2022
    Article
  6. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

9 authors at 5 institutions in 1 country.

Dong-Gen LuoSolomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA. Electronic address: dgluo@pku.edu.cn.
Daniel SilvermanSolomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Biochemistry, Cellular and Molecular Biology Graduate Program, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
Rikard FrederiksenJules Stein Eye Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA.
Rajan AdhikariDepartment of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118, USA.
Li-Hui CaoSolomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
John E OatisDepartment of Ophthalmology, Medical University of South Carolina, Charleston, SC 29425, USA.
Masahiro KonoDepartment of Ophthalmology, Medical University of South Carolina, Charleston, SC 29425, USA.
M Carter CornwallDepartment of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118, USA.
King-Wai YauSolomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA. Electronic address: kwyau@jhmi.edu.
Johns Hopkins Medicine · USBoston University · USMedical University of South Carolina · USDoheny Eye Institute · USJohns Hopkins University · US

Funding

VISUAL TRANSDUCTION IN RETINAL PHOTORECEPTORSR01EY006837 · NEI · JOHNS HOPKINS UNIVERSITY · PI KING-WAI YAU · 1987 to 2026
$8.5M
Spectral & Metabolic Basis of Visual ResponsesR01EY001157 · NEI · BOSTON UNIVERSITY MEDICAL CAMPUS · PI CORNWALL, M CARTER · 1985 to 2020
$8.3M
Visual Science Training ProgramT32EY007143 · NEI · JOHNS HOPKINS UNIVERSITY · PI Laura Ensign, JEREMY NATHANS · 1995 to 2026
$6.2M
NEI NIH HHS R01 EY001157NEI NIH HHS R01 EY006837NEI NIH HHS T32 EY007143
6 · The paper itself

Abstract

Retinal rod and cone photoreceptors mediate vision in dim and bright light, respectively, by transducing absorbed photons into neural electrical signals. Their phototransduction mechanisms are essentially identical. However, one difference is that, whereas a rod visual pigment remains stable in darkness, a cone pigment has some tendency to dissociate spontaneously into apo-opsin and retinal (the chromophore) without isomerization. This cone-pigment property is long known but has mostly been overlooked. Importantly, because apo-opsin has weak constitutive activity, it triggers transduction to produce electrical noise even in darkness. Currently, the precise dark apo-opsin contents across cone subtypes are mostly unknown, as are their dark activities. We report here a study of goldfish red (L), green (M), and blue (S) cones, finding with microspectrophotometry widely different apo-opsin percentages in darkness, being ∼30% in L cones, ∼3% in M cones, and negligible in S cones. L and M cones also had higher dark apo-opsin noise than holo-pigment thermal isomerization activity. As such, given the most likely low signal amplification at the pigment-to-transducin/phosphodiesterase phototransduction step, especially in L cones, apo-opsin noise may not be easily distinguishable from light responses and thus may affect cone vision near threshold.

Indexed as

DarknessAnimalsGoldfishLight Signal TransductionModels, AnimalOpsinsPatch-Clamp TechniquesPhotic StimulationRetinal Cone Photoreceptor CellsSingle-Cell AnalysisOpsinscone photodetection thresholdcone phototransductionconstitutive apo-opsin activitydark noisetruncated-cone recording

Identifiers

PMID33065015
PMCPMC8561704
OpenAlexW3093230432

What OpenQuestion holds

Textmetadata
LicenceTDM
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.