Journal
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
Volume 22, Issue 21, Pages -Publisher
MDPI
DOI: 10.3390/ijms222111514
Keywords
Orai1; immunological synapse; calcium signaling; STIM1; SAP97
Funding
- European Union and the European Regional Development Fund [GINOP-2.3.2-15-2016-00044, NKFIH K128525, K119417]
- Bolyai Janos Fellowship [BM 1406, EFOP-3.6.2-16-2017-00006, EFOP-3.6.3-VEKOP-16-2017-00009, GINOP-2.3.2-15-2016-00020]
Ask authors/readers for more resources
The study investigates how adapter proteins regulate the residence of Orai1 at the immunological synapse in T cells, revealing that SAP97 may contribute to the short-lived IS residence of Orai1, and that the binding of STIM1 to the Orai1 N-terminus is necessary for SAP97-Orai1 interaction.
CRAC, which plays important role in Ca2+-dependent T-lymphocyte activation, is composed of the ER-resident STIM1 and the plasma membrane Orai1 pore-forming subunit. Both accumulate at the immunological synapse (IS) between a T cell and an antigen-presenting cell (APC). We hypothesized that adapter/interacting proteins regulate Orai1 residence in the IS. We could show that mGFP-tagged Orai1-Full channels expressed in Jurkat cells had a biphasic IS-accumulation kinetics peaked at 15 min. To understand the background of Orai1 IS-redistribution we knocked down STIM1 and SAP97 (adaptor protein with a short IS-residency (15 min) and ability to bind Orai1 N-terminus): the mGFP-Orai1-Full channels kept on accumulating in the IS up to the 60th minute in the STIM1- and SAP97-lacking Jurkat cells. Deletion of Orai1 N terminus (mGFP-Orai1-& UDelta;72) resulted in the same time course as described for STIM1/SAP97 knock-down cells. Ca2+-imaging of IS-engaged T-cells revealed that of Orai1 residency modifies the Ca2+-response: cells expressing mGFP-Orai1-& UDelta;72 construct or mGFP-Orai1-Full in SAP-97 knock-down cells showed higher number of Ca2+-oscillation up to the 90th minute after IS formation. Overall, these data suggest that SAP97 may contribute to the short-lived IS-residency of Orai1 and binding of STIM1 to Orai1 N-terminus is necessary for SAP97-Orai1 interaction.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available