Unraveling aquaporin interaction partners

• Published in: Biochimica et biophysica acta Vol. 1840; no. 5; pp. 1614 - 1623
• Main Authors: Sjöhamn, Jennie, Hedfalk, Kristina
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.05.2014
• Subjects: Aquaporin; aquaporins; Aquaporins - chemistry; Aquaporins - metabolism; Chemical Sciences; Co-precipitation; coprecipitation; direct contact; fluorescence; humans; Kemi; Membrane protein; molecular biology; physiology; Protein Binding; protein-protein interactions; Protein–protein interaction; screening; two hybrid system techniques; Yeast two-hybrid interaction assay; AQP; GFP; Membrane protein; IHC; IP; ICC; PPI; Yeast two-hybrid interaction assay; YTH; Co-precipitation; Aquaporin; Protein–protein interaction
• ISSN: 0304-4165; 0006-3002; 1872-8006
• DOI: 10.1016/j.bbagen.2013.11.012

Insight into protein–protein interactions (PPIs) is highly desirable in order to understand the physiology of cellular events. This understanding is one of the challenges in biochemistry and molecular biology today, especially for eukaryotic membrane proteins where hurdles of production, purification and structural determination must be passed. We have explored the common strategies used to find medically relevant interaction partners of aquaporins (AQPs). The most frequently used methods to detect direct contact, yeast two-hybrid interaction assay and co-precipitation, are described together with interactions specifically found for the selected targets AQP0, AQP2, AQP4 and AQP5. The vast majority of interactions involve the aquaporin C-terminus and the characteristics of the interaction partners are strikingly diverse. While the well-established methods for PPIs are robust, a novel approach like bimolecular fluorescence complementation (BiFC) is attractive for screening many conditions as well as transient interactions. The ultimate goal is structural evaluation of protein complexes in order to get mechanistic insight into how proteins communicate at a molecular level. What we learn from the human aquaporin field in terms of method development and communication between proteins can be of major use for any integral membrane protein of eukaryotic origin. This article is part of a Special Issue entitled Aquaporins. •AQPs can regulate each other having implications in tissues with several isoforms.•Structural analysis of protein complexes provides molecular insight into regulation.•The majority of the human AQPs can be produced recombinantly to high-yields.