A developmental switch in the expression of aquaporin-4 and Kir4.1 from horizontal to Müller cells in mouse retina

Alejandra Bosco, Karen Cusato, Grazia P. Niccbia, Antonio Frigeri, David C. Spray

Research output: Contribution to journalArticle

31 Citations (Scopus)

Abstract

PURPOSE. In adult retina, aquaporin-4 (AQP4) and inwardly rectifying K + (Kir4.1) channels localize to astrocyte and Müller cell membranes facing vascular and vitreous compartments, optimizing clearance of extracellular K+ and water from the synaptic layers. However, it is unknown whether these channels are expressed at early developmental stages, before gliogenesis or angiogenesis take place in the neural retina. This study was conducted to determine the presence of AQP4 and Kir4.1 proteins in the developing mouse retina. METHODS. Simultaneous AQP4 and Kir4.1 immunodetection was performed in postnatal mice 1, 9, 15, and 30 days of age. Confocal microscopy was used to identify the cellular distribution of AQP4 and Kir4.1 proteins, as well as their coexpression with the cell-selective immunomarkers Prox-1, calbindin, and neurofilament. RESULTS. AQP4 and Kir4.1 proteins were coexpressed in calbindin- and Prox1-expressing retinal neurons at birth. These neurons were identified as horizontal cells based on their position and morphology. By P15, when vision starts, AQP4 and Kir4.1 localization coordinately switched from horizontal cells to Müller glial cells. CONCLUSIONS. The findings showed that AQP4 and Kir4.1 protein expression is confined to differentiating horizontal cells before its expression in Müller cells. The finding of AQP4 in neurons is novel, since AQP4 expression within the central nervous system is restricted to glia. Also, the results demonstrated that AQP4 is a horizontal cell-specific immuno-marker in neonatal retina. The transitory coexpression of AQP4 and Kir4.1 proteins by differentiating horizontal interneurons suggests that these cells mediate K+ and water transcellular uptake until the initiation of phototransduction, when glial cells assume these functions.

Original languageEnglish (US)
Pages (from-to)3869-3875
Number of pages7
JournalInvestigative Ophthalmology and Visual Science
Volume46
Issue number10
DOIs
StatePublished - Oct 2005

Fingerprint

Aquaporin 4
Retina
Neuroglia
Calbindins
Light Signal Transduction
Inwardly Rectifying Potassium Channel
Retinal Neurons
Neurons
Naproxen
Intermediate Filaments
Water
Interneurons
Confocal Microscopy
Astrocytes
Blood Vessels
Central Nervous System

ASJC Scopus subject areas

  • Ophthalmology

Cite this

A developmental switch in the expression of aquaporin-4 and Kir4.1 from horizontal to Müller cells in mouse retina. / Bosco, Alejandra; Cusato, Karen; Niccbia, Grazia P.; Frigeri, Antonio; Spray, David C.

In: Investigative Ophthalmology and Visual Science, Vol. 46, No. 10, 10.2005, p. 3869-3875.

Research output: Contribution to journalArticle

Bosco, Alejandra ; Cusato, Karen ; Niccbia, Grazia P. ; Frigeri, Antonio ; Spray, David C. / A developmental switch in the expression of aquaporin-4 and Kir4.1 from horizontal to Müller cells in mouse retina. In: Investigative Ophthalmology and Visual Science. 2005 ; Vol. 46, No. 10. pp. 3869-3875.
@article{5a3d84b99f8e49d19ec26283f4e09ee9,
title = "A developmental switch in the expression of aquaporin-4 and Kir4.1 from horizontal to M{\"u}ller cells in mouse retina",
abstract = "PURPOSE. In adult retina, aquaporin-4 (AQP4) and inwardly rectifying K + (Kir4.1) channels localize to astrocyte and M{\"u}ller cell membranes facing vascular and vitreous compartments, optimizing clearance of extracellular K+ and water from the synaptic layers. However, it is unknown whether these channels are expressed at early developmental stages, before gliogenesis or angiogenesis take place in the neural retina. This study was conducted to determine the presence of AQP4 and Kir4.1 proteins in the developing mouse retina. METHODS. Simultaneous AQP4 and Kir4.1 immunodetection was performed in postnatal mice 1, 9, 15, and 30 days of age. Confocal microscopy was used to identify the cellular distribution of AQP4 and Kir4.1 proteins, as well as their coexpression with the cell-selective immunomarkers Prox-1, calbindin, and neurofilament. RESULTS. AQP4 and Kir4.1 proteins were coexpressed in calbindin- and Prox1-expressing retinal neurons at birth. These neurons were identified as horizontal cells based on their position and morphology. By P15, when vision starts, AQP4 and Kir4.1 localization coordinately switched from horizontal cells to M{\"u}ller glial cells. CONCLUSIONS. The findings showed that AQP4 and Kir4.1 protein expression is confined to differentiating horizontal cells before its expression in M{\"u}ller cells. The finding of AQP4 in neurons is novel, since AQP4 expression within the central nervous system is restricted to glia. Also, the results demonstrated that AQP4 is a horizontal cell-specific immuno-marker in neonatal retina. The transitory coexpression of AQP4 and Kir4.1 proteins by differentiating horizontal interneurons suggests that these cells mediate K+ and water transcellular uptake until the initiation of phototransduction, when glial cells assume these functions.",
author = "Alejandra Bosco and Karen Cusato and Niccbia, {Grazia P.} and Antonio Frigeri and Spray, {David C.}",
year = "2005",
month = "10",
doi = "10.1167/iovs.05-0385",
language = "English (US)",
volume = "46",
pages = "3869--3875",
journal = "Investigative Ophthalmology and Visual Science",
issn = "0146-0404",
publisher = "Association for Research in Vision and Ophthalmology Inc.",
number = "10",

}

TY - JOUR

T1 - A developmental switch in the expression of aquaporin-4 and Kir4.1 from horizontal to Müller cells in mouse retina

AU - Bosco, Alejandra

AU - Cusato, Karen

AU - Niccbia, Grazia P.

AU - Frigeri, Antonio

AU - Spray, David C.

PY - 2005/10

Y1 - 2005/10

N2 - PURPOSE. In adult retina, aquaporin-4 (AQP4) and inwardly rectifying K + (Kir4.1) channels localize to astrocyte and Müller cell membranes facing vascular and vitreous compartments, optimizing clearance of extracellular K+ and water from the synaptic layers. However, it is unknown whether these channels are expressed at early developmental stages, before gliogenesis or angiogenesis take place in the neural retina. This study was conducted to determine the presence of AQP4 and Kir4.1 proteins in the developing mouse retina. METHODS. Simultaneous AQP4 and Kir4.1 immunodetection was performed in postnatal mice 1, 9, 15, and 30 days of age. Confocal microscopy was used to identify the cellular distribution of AQP4 and Kir4.1 proteins, as well as their coexpression with the cell-selective immunomarkers Prox-1, calbindin, and neurofilament. RESULTS. AQP4 and Kir4.1 proteins were coexpressed in calbindin- and Prox1-expressing retinal neurons at birth. These neurons were identified as horizontal cells based on their position and morphology. By P15, when vision starts, AQP4 and Kir4.1 localization coordinately switched from horizontal cells to Müller glial cells. CONCLUSIONS. The findings showed that AQP4 and Kir4.1 protein expression is confined to differentiating horizontal cells before its expression in Müller cells. The finding of AQP4 in neurons is novel, since AQP4 expression within the central nervous system is restricted to glia. Also, the results demonstrated that AQP4 is a horizontal cell-specific immuno-marker in neonatal retina. The transitory coexpression of AQP4 and Kir4.1 proteins by differentiating horizontal interneurons suggests that these cells mediate K+ and water transcellular uptake until the initiation of phototransduction, when glial cells assume these functions.

AB - PURPOSE. In adult retina, aquaporin-4 (AQP4) and inwardly rectifying K + (Kir4.1) channels localize to astrocyte and Müller cell membranes facing vascular and vitreous compartments, optimizing clearance of extracellular K+ and water from the synaptic layers. However, it is unknown whether these channels are expressed at early developmental stages, before gliogenesis or angiogenesis take place in the neural retina. This study was conducted to determine the presence of AQP4 and Kir4.1 proteins in the developing mouse retina. METHODS. Simultaneous AQP4 and Kir4.1 immunodetection was performed in postnatal mice 1, 9, 15, and 30 days of age. Confocal microscopy was used to identify the cellular distribution of AQP4 and Kir4.1 proteins, as well as their coexpression with the cell-selective immunomarkers Prox-1, calbindin, and neurofilament. RESULTS. AQP4 and Kir4.1 proteins were coexpressed in calbindin- and Prox1-expressing retinal neurons at birth. These neurons were identified as horizontal cells based on their position and morphology. By P15, when vision starts, AQP4 and Kir4.1 localization coordinately switched from horizontal cells to Müller glial cells. CONCLUSIONS. The findings showed that AQP4 and Kir4.1 protein expression is confined to differentiating horizontal cells before its expression in Müller cells. The finding of AQP4 in neurons is novel, since AQP4 expression within the central nervous system is restricted to glia. Also, the results demonstrated that AQP4 is a horizontal cell-specific immuno-marker in neonatal retina. The transitory coexpression of AQP4 and Kir4.1 proteins by differentiating horizontal interneurons suggests that these cells mediate K+ and water transcellular uptake until the initiation of phototransduction, when glial cells assume these functions.

UR - http://www.scopus.com/inward/record.url?scp=32944475270&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=32944475270&partnerID=8YFLogxK

U2 - 10.1167/iovs.05-0385

DO - 10.1167/iovs.05-0385

M3 - Article

VL - 46

SP - 3869

EP - 3875

JO - Investigative Ophthalmology and Visual Science

JF - Investigative Ophthalmology and Visual Science

SN - 0146-0404

IS - 10

ER -