Evidence map›Paper›PMID 33049058›Full record

ArticleInvestigative ophthalmology & visual science2020

Protein Phosphatase 2A and Clathrin-Mediated Endocytosis Facilitate Robust Melanopsin Light Responses and Resensitization.

Juan C Valdez-Lopez, Meheret Gebreegziabher, Robin J Bailey, Jair Flores, Olanike Awotunde, Thomas Burnett, Phyllis R Robinson

Open access · goldAbstract read
In one paragraph

Article in Investigative ophthalmology & visual science, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 3 papers.

0numbers the graph read from it
0cells of the map it votes in
3citing papers in PubMed
0.2field-weighted citation impact, top 49% 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

3 citing papers in PubMed, 4 citations in OpenAlex.

  1. Divergence of Melanopsin's Intrinsic Properties and Downstream Actions.bioRxiv : the preprint server for biology · 2026
    Article
  2. Article
  3. The Multistable Melanopsins of Mammals.Frontiers in ophthalmology · 2023
    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

7 authors at 2 institutions in 1 country.

Juan C Valdez-LopezDepartment of Biological Sciences, University of Maryland Baltimore County, Baltimore, Maryland, United States.
Meheret GebreegziabherDepartment of Biological Sciences, University of Maryland Baltimore County, Baltimore, Maryland, United States.
Robin J BaileyDepartment of Biological Sciences, University of Maryland Baltimore County, Baltimore, Maryland, United States.
Jair FloresDepartment of Biological Sciences, University of Maryland Baltimore County, Baltimore, Maryland, United States.
Olanike AwotundeDepartment of Biological Sciences, University of Maryland Baltimore County, Baltimore, Maryland, United States.
Thomas BurnettDepartment of Biological Sciences, University of Maryland Baltimore County, Baltimore, Maryland, United States.
Phyllis R RobinsonDepartment of Biological Sciences, University of Maryland Baltimore County, Baltimore, Maryland, United States.
University of Maryland, Baltimore County · USNational Human Genome Research Institute · US

Funding

The MARC U*STAR Program at UMBCT34GM008663 · NIGMS · UNIVERSITY OF MARYLAND BALTIMORE COUNTY · PI ROBINSON, PHYLLIS R · 1997 to 2019
$21.9M
EXPAND PARTICIPATION BY MINORITIES IN BIOMEDICAL SCIENCER25GM055036 · NIGMS · UNIVERSITY OF MARYLAND BALTIMORE COUNTY · PI SUMMERS, MICHAEL FINLEY · 1996 to 2021
$16.9M
Regulation of the intrinsic melanopsin-based light response in ipRGCsR01EY027202 · NEI · UNIVERSITY OF MARYLAND BALTIMORE COUNTY · PI RONALD Lane BROWN, Joseph Leffler · 2017 to 2026
$5.3M
Graduate Training at The Chemistry Biology InterfaceT32GM066706 · NIGMS · UNIVERSITY OF MARYLAND BALTIMORE COUNTY · PI SELEY-RADTKE, KATHERINE L, SMITH, AARON T · 2004 to 2023
$3.3M
Molecular characterization of mouse melanopsin and second messenger pathway.R01EY019053 · NEI · UNIVERSITY OF MARYLAND BALTIMORE COUNTY · PI ROBINSON, PHYLLIS R · 2009 to 2012
$1.2M
NEI NIH HHS R01 EY019053NEI NIH HHS R01 EY027202NIGMS NIH HHS R25 GM055036NIGMS NIH HHS T32 GM066706NIGMS NIH HHS T34 GM008663
6 · The paper itself

Abstract

Purpose: Intrinsically photosensitive retinal ganglion cells (ipRGCs) that express the visual pigment melanopsin regulate non-image-forming visual tasks, such as circadian photoentrainment and pupil constriction, as well as contrast detection for image formation. Sustained ipRGC function throughout the day is, therefore, of great importance. Melanopsin is a bistable rhabdomeric-type (R-type) visual pigment, which is thought to use light to regenerate its chromophore from all-trans-retinal back to 11-cis-retinal and does not depend on constant chromophore supply to the extent required by visual pigment in rod and cone photoreceptors. Like the majority of photopigments and G-protein-coupled receptors (GPCRs), melanopsin deactivation requires C-terminal phosphorylation and subsequent β-arrestin binding. We hypothesize that melanopsin utilizes canonical GPCR resensitization mechanisms, including dephosphorylation and endocytosis, during the light, and together, they provide a mechanism for prolonged light responses. Methods: Here, we examined expression of protein phosphatases from a variety of subfamilies by RT-PCR and immunohistochemical analyses of the mouse retina. The expression of protein phosphatase 2A (PP2A) in ipRGCs was assessed. We also examine the role of phosphatase and endocytic activity in sustaining melanopsin signaling using transiently-transfected HEK293 cells. Results: Our analyses suggest that melanopsin-mediated light responses can be rapidly and extensively enhanced by PP2A activity. Light-activated melanopsin undergoes endocytosis in a clathrin-dependent manner. This endocytic activity enhances light responses upon repeated stimulation, implicating a role for endocytic activity in resensitization. Conclusions: Thus, we propose that melanopsin phototransduction is maintained by utilizing canonical GPCR resensitization mechanisms rather than reliance on chromophore replenishment from supporting cells.

Indexed as

AnimalsCalcium SignalingClathrinEndocytosisGene Expression RegulationHEK293 CellsHumansMelanopsinMiceMice, Inbred C57BLMicroscopy, ConfocalPhotic StimulationPlasmidsProtein Phosphatase 2Real-Time Polymerase Chain ReactionRetinal Ganglion CellsClathrinMelanopsinProtein Phosphatase 2RNA, MessengerRod Opsins

Identifiers

PMID33049058
PMCPMC7571330
OpenAlexW3092588387

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC-ND
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.