Insights into cell surface expression, supramolecular organization, and functions of aquaporin 4 isoforms in astrocytes

Jorgačevski, Jernej (author), Zorec, Robert (author), Potokar, Maja (author)

Aquaporin 4 (AQP4) is the most abundant water channel in the central nervous system (CNS). Its expression is confined to non-neuronal glial cells, predominantly to astrocytes that represent a heterogeneous glial cell type in the CNS. The membrane of astrocyte processes, which align brain capillaries and pia, is particularly rich in AQP4. Several isoforms of AQP4 have been described; however, only some (AQP4a (M1), AQP4 c (M23), AQP4e, and AQP4ex) have been identified in the plasma membrane assemblies of astrocytes termed orthogonal arrays of particles (OAPs). Intracellular splicing isoforms (AQP4b, AQP4d, AQP4f, AQP4-∆4) have been documented, and most of them are postulated to have a role in the cell surface distribution of the plasma membrane isoforms and in the formation of OAPs in murine and human astrocytes. Although OAPs have been proposed to play various roles in the functioning of astrocytes and CNS tissue as a whole, many of these still need to be described. OAPs are studied primarily from the perspective of understanding water permeability regulation through the plasma membrane and of their involvement in cell adhesion and in the dynamics of astrocytic processes. This review describes the cellular distribution of various AQP4 isoforms and their implications in OAP assembly, which is regulated by several intracellular and extracellular proteins.

• Language: English
• Keywords: aquaporin 4 (AQP4), astrocyte, brain edema, glia, orthogonal arrays of particles (OAP), cell migration, extracellular matrix, hormones
• Work type: Article
• Typology: 1.02 - Review Article
• Organization: MF - Faculty of Medicine
• Publication status: Published
• Publication version: Version of Record
• Year: 2020
• Number of pages: 19 str.
• Numbering: Vol. 9, iss. 12, art. 2622
• PID: 20.500.12556/RUL-134806
• UDC: 616-092
• ISSN on article: 2073-4409
• DOI: 10.3390/cells9122622
• COBISS.SI-ID: 41327875
• Publication date in RUL: 02.02.2022

Record is a part of a journal

• Title: Cells
• Shortened title: Cells
• Publisher: MDPI
• ISSN: 2073-4409
• COBISS.SI-ID: 519958809

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 07.12.2020

Secondary language

• Language: Slovenian
• Keywords: akvaporin 4 (AQP4), astrocit, edem možganov

Projects

• Funder: ARRS - Slovenian Research Agency
• Project number: P3-0310
• Name: Celična fiziologija

• Funder: ARRS - Slovenian Research Agency
• Project number: J3-9266
• Name: Uravnavanje fuzijske pore in motnje skladiščenja v lizosomih