The Readthrough Isoform AQP4ex Is Constitutively Phosphorylated in the Perivascular Astrocyte Endfeet of Human Brain.

ABSTRACT: AQP4ex is a recently discovered isoform of AQP4 generated by a translational readthrough mechanism. It is strongly expressed at the astrocyte perivascular endfeet as a component of the supramolecular membrane complex, commonly called orthogonal array of particles (OAP), together with the canonical isoforms M1 and M23 of AQP4. Previous site-directed mutagenesis experiments suggested the potential role of serine³³¹ and serine³³⁵, located in the extended peptide of AQP4ex, in water channel activity by phosphorylation. In the present study we evaluated the effective phosphorylation of human AQP4ex. A small scale bioinformatic analysis indicated that only Ser³³⁵ is conserved in human, mouse and rat AQP4ex. The phosphorylation site of Ser³³⁵ was assess

SUBMITTER: Pati R 

PROVIDER: S-EPMC9138620 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature