PMID- 33372133
OWN - NLM
STAT- MEDLINE
DCOM- 20210510
LR  - 20210629
IS  - 1091-6490 (Electronic)
IS  - 0027-8424 (Print)
IS  - 0027-8424 (Linking)
VI  - 118
IP  - 2
DP  - 2021 Jan 12
TI  - SCAMP5 plays a critical role in axonal trafficking and synaptic localization of 
      NHE6 to adjust quantal size at glutamatergic synapses.
LID - 10.1073/pnas.2011371118 [doi]
LID - e2011371118
AB  - Glutamate uptake into synaptic vesicles (SVs) depends on cation/H(+) exchange 
      activity, which converts the chemical gradient (DeltapH) into membrane potential (Deltapsi) 
      across the SV membrane at the presynaptic terminals. Thus, the proper recruitment 
      of cation/H(+) exchanger to SVs is important in determining glutamate quantal 
      size, yet little is known about its localization mechanism. Here, we found that 
      secretory carrier membrane protein 5 (SCAMP5) interacted with the cation/H(+) 
      exchanger NHE6, and this interaction regulated NHE6 recruitment to glutamatergic 
      presynaptic terminals. Protein-protein interaction analysis with truncated 
      constructs revealed that the 2/3 loop domain of SCAMP5 is directly associated 
      with the C-terminal region of NHE6. The use of optical imaging and 
      electrophysiological recording showed that small hairpin RNA-mediated knockdown 
      (KD) of SCAMP5 or perturbation of SCAMP5/NHE6 interaction markedly inhibited 
      axonal trafficking and the presynaptic localization of NHE6, leading to 
      hyperacidification of SVs and a reduction in the quantal size of glutamate 
      release. Knockout of NHE6 occluded the effect of SCAMP5 KD without causing 
      additional defects. Together, our results reveal that as a key regulator of 
      axonal trafficking and synaptic localization of NHE6, SCAMP5 could adjust 
      presynaptic strength by regulating quantal size at glutamatergic synapses. Since 
      both proteins are autism candidate genes, the reduced quantal size by 
      interrupting their interaction may underscore synaptic dysfunction observed in 
      autism.
FAU - Lee, Unghwi
AU  - Lee U
AUID- ORCID: 0000-0002-9956-7570
AD  - Department of Physiology and Biomedical Sciences, Seoul National University 
      College of Medicine, Seoul 03080, South Korea.
FAU - Choi, Chunghon
AU  - Choi C
AUID- ORCID: 0000-0002-9250-2651
AD  - Department of Physiology and Biomedical Sciences, Seoul National University 
      College of Medicine, Seoul 03080, South Korea.
FAU - Ryu, Seung Hyun
AU  - Ryu SH
AUID- ORCID: 0000-0002-6787-8243
AD  - Department of Physiology and Biomedical Sciences, Seoul National University 
      College of Medicine, Seoul 03080, South Korea.
FAU - Park, Daehun
AU  - Park D
AD  - Department of Physiology and Biomedical Sciences, Seoul National University 
      College of Medicine, Seoul 03080, South Korea.
FAU - Lee, Sang-Eun
AU  - Lee SE
AUID- ORCID: 0000-0001-7371-8556
AD  - Department of Physiology and Biomedical Sciences, Seoul National University 
      College of Medicine, Seoul 03080, South Korea.
AD  - Neuroscience Research Institute, Seoul National University College of Medicine, 
      Seoul 03080, South Korea.
FAU - Kim, Kitae
AU  - Kim K
AD  - Department of Physiology and Biomedical Sciences, Seoul National University 
      College of Medicine, Seoul 03080, South Korea.
FAU - Kim, Yujin
AU  - Kim Y
AUID- ORCID: 0000-0002-4840-9011
AD  - Department of Physiology and Biomedical Sciences, Seoul National University 
      College of Medicine, Seoul 03080, South Korea.
AD  - Neuroscience Research Institute, Seoul National University College of Medicine, 
      Seoul 03080, South Korea.
FAU - Chang, Sunghoe
AU  - Chang S
AD  - Department of Physiology and Biomedical Sciences, Seoul National University 
      College of Medicine, Seoul 03080, South Korea; sunghoe@snu.ac.kr.
AD  - Neuroscience Research Institute, Seoul National University College of Medicine, 
      Seoul 03080, South Korea.
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Proc Natl Acad Sci U S A
JT  - Proceedings of the National Academy of Sciences of the United States of America
JID - 7505876
RN  - 0 (Membrane Proteins)
RN  - 0 (SCAMP5 protein, human)
RN  - 0 (SLC9A6 protein, human)
RN  - 0 (Sodium-Hydrogen Exchangers)
RN  - 3KX376GY7L (Glutamic Acid)
SB  - IM
MH  - Axons/metabolism
MH  - Biological Transport
MH  - Cell Line
MH  - Excitatory Postsynaptic Potentials/physiology
MH  - Glutamic Acid/*metabolism
MH  - HEK293 Cells
MH  - Humans
MH  - Membrane Proteins/*metabolism/physiology
MH  - Patch-Clamp Techniques
MH  - Presynaptic Terminals/physiology
MH  - Protein Transport
MH  - Sodium-Hydrogen Exchangers/*metabolism/physiology
MH  - Synapses/metabolism
MH  - Synaptic Transmission/physiology
MH  - Synaptic Vesicles/metabolism
PMC - PMC7812776
OTO - NOTNLM
OT  - NHE6
OT  - SCAMP5
OT  - autism
OT  - presynaptic terminal
OT  - quantal size
COIS- The authors declare no competing interest.
EDAT- 2020/12/30 06:00
MHDA- 2021/05/11 06:00
PMCR- 2021/06/28
CRDT- 2020/12/29 06:01
PHST- 2020/12/29 06:01 [entrez]
PHST- 2020/12/30 06:00 [pubmed]
PHST- 2021/05/11 06:00 [medline]
PHST- 2021/06/28 00:00 [pmc-release]
AID - 2011371118 [pii]
AID - 202011371 [pii]
AID - 10.1073/pnas.2011371118 [doi]
PST - ppublish
SO  - Proc Natl Acad Sci U S A. 2021 Jan 12;118(2):e2011371118. doi: 
      10.1073/pnas.2011371118.