Related Experiment Videos
beta-Arrestins bind and decrease cell-surface abundance of the Na+/H+ exchanger NHE5 isoform
Elöd Z Szabó1, Masayuki Numata, Viktoria Lukashova
1Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
Summary
Beta-arrestins bind to the Na(+)/H(+) exchanger NHE5, influencing its cellular location. This interaction, involving beta-arrestin1 and beta-arrestin2, reduces NHE5 at the cell surface, revealing a new role for arrestins in protein trafficking.
Area of Science:
- Cell Biology
- Molecular Biology
- Neuroscience
Background:
- The Na(+)/H(+) exchanger NHE5 is found in neuronal plasma membranes and recycling vesicles.
- Its internalization involves clathrin-mediated endocytosis.
Purpose of the Study:
- To identify proteins interacting with the C-terminal region of NHE5.
- To elucidate the molecular mechanisms of NHE5 trafficking.
Main Methods:
- Yeast two-hybrid screening of a human brain cDNA library.
- GST pull-down assays for in vitro interaction validation.
- Co-immunoprecipitation in transfected cells to confirm in-cell association.
Main Results:
- Beta-arrestin2 was identified as an NHE5-interacting protein.
- Direct binding between NHE5 and beta-arrestin2 was confirmed in vitro and in cells.
- Co-expression of NHE5 and beta-arrestin2 led to NHE5 accumulation in vesicles and reduced cell surface levels.
- Beta-arrestin1 yielded similar results.
Conclusions:
- Beta-arrestins interact with the neuronal Na(+)/H(+) exchanger NHE5.
- This interaction influences NHE5 trafficking and cell surface abundance.
- Arrestins play a broader role in integral plasma membrane protein trafficking than previously understood.