水通道蛋白 6 的第三细胞外环内的一个区域可阻止其在异源细胞系中向质膜转运。

A region within the third extracellular loop of rat Aquaporin 6 precludes trafficking to plasma membrane in a heterologous cell line.

机构信息

The Department of Neurosurgery, Case Western Reserve University, Cleveland, USA.

Department of Physiology and Biophysics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH, 44106-4965, USA.

出版信息

Sci Rep. 2021 Jul 1;11(1):13673. doi: 10.1038/s41598-021-93117-8.

DOI:10.1038/s41598-021-93117-8

PMID:34211055

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC8249660/

Abstract

The inability to over-express Aquaporin 6 (AQP6) in the plasma membrane of heterologous cells has hampered efforts to further characterize the function of this aquaglyceroporin membrane protein at atomic detail using crystallographic approaches. Using an Aquaporin 3-tGFP Reporter (AGR) system we have identified a region within loop C of AQP6 that is responsible for severely hampering plasma membrane expression. Serine substitution corroborated that amino acids present within AQP6 of AQP6 loop C contribute to intracellular endoplasmic reticulum (ER) retention. This intracellular retention signal may preclude proper plasma membrane trafficking and severely curtail expression of AQP6 in heterologous expression systems.

摘要

无法在异源细胞的质膜中过表达水通道蛋白 6（AQP6），这阻碍了使用晶体学方法进一步表征这种水甘油通道蛋白膜蛋白的原子细节功能。使用水通道蛋白 3-tGFP 报告器（AGR）系统，我们已经确定了 AQP6 环 C 内的一个区域，该区域负责严重阻碍质膜表达。丝氨酸取代证实了 AQP6 环 C 中的氨基酸有助于细胞内内质网（ER）保留。这种细胞内保留信号可能阻止了质膜的正确运输，并严重限制了异源表达系统中 AQP6 的表达。