Dataset Information

Depletion of 14-3-3? reduces the surface expression of Transient Receptor Potential Melastatin 4b (TRPM4b) channels and attenuates TRPM4b-mediated glutamate-induced neuronal cell death.

ABSTRACT:

Background

TRPM4 channels are Ca2+-activated nonselective cation channels which are deeply involved in physiological and pathological conditions. However, their trafficking mechanism and binding partners are still elusive.

Results

We have found the 14-3-3? as a binding partner for TRPM4b using its N-terminal fragment from the yeast-two hybrid screening. Ser88 at the N-terminus of TRPM4b is critical for 14-3-3? binding by showing GST pull-down and co-immunoprecipitation. Heterologous overexpression of 14-3-3? in HEK293T cells increased TRPM4b expression on the plasma membrane which was measured by whole-cell recordings and cell surface biotinylation experiment. Surface expression of TRPM4b was greatly reduced by short hairpin RNA (shRNA) against 14-3-3?. Next, endogenous TRPM4b-mediated currents were electrophysiologically characterized by application of glutamate and 9-phenanthrol, a TRPM4b specific antagonist in HT-22 cells which originated from mouse hippocampal neurons. Glutamate-induced TRPM4b currents were significantly attenuated by shRNAs against 14-3-3? or TRPM4b in these cells. Finally, glutamate-induced cell death was greatly prevented by treatment of 9-phenanthrol or 14-3-3? shRNA.

Conclusion

These results showed that the cell surface expression of TRPM4 channels is mediated by 14-3-3? binding, and the specific inhibition of this trafficking process can be a potential therapeutic target for glutamate-induced neuronal cell death.

SUBMITTER: Cho CH

PROVIDER: S-EPMC4115172 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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Publications

Depletion of 14-3-3γ reduces the surface expression of Transient Receptor Potential Melastatin 4b (TRPM4b) channels and attenuates TRPM4b-mediated glutamate-induced neuronal cell death.

Cho Chang-Hoon CH Kim Eunju E Lee Young-Sun YS Yarishkin Oleg O Yoo Jae Cheal JC Park Jae-Yong JY Hong Seong-Geun SG Hwang Eun Mi EM

Molecular brain 20140722

<h4>Background</h4>TRPM4 channels are Ca2+-activated nonselective cation channels which are deeply involved in physiological and pathological conditions. However, their trafficking mechanism and binding partners are still elusive.<h4>Results</h4>We have found the 14-3-3γ as a binding partner for TRPM4b using its N-terminal fragment from the yeast-two hybrid screening. Ser88 at the N-terminus of TRPM4b is critical for 14-3-3γ binding by showing GST pull-down and co-immunoprecipitation. Heterologo ...[more]

PMID: 25047048

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