PMID- 36509140
OWN - NLM
STAT- MEDLINE
DCOM- 20230131
LR  - 20230622
IS  - 1083-351X (Electronic)
IS  - 0021-9258 (Print)
IS  - 0021-9258 (Linking)
VI  - 299
IP  - 1
DP  - 2023 Jan
TI  - Leucine 434 is essential for docosahexaenoic acid-induced augmentation of 
      L-glutamate transporter current.
PG  - 102793
LID - S0021-9258(22)01236-4 [pii]
LID - 10.1016/j.jbc.2022.102793 [doi]
LID - 102793
AB  - Astrocytic excitatory amino acid transporter 2 (EAAT2) plays a major role in 
      removing the excitatory neurotransmitter L-glutamate (L-Glu) from synaptic clefts 
      in the forebrain to prevent excitotoxicity. Polyunsaturated fatty acids such as 
      docosahexaenoic acid (DHA, 22:6 n-3) enhance synaptic transmission, and their 
      target molecules include EAATs. Here, we aimed to investigate the effect of DHA 
      on EAAT2 and identify the key amino acid for DHA/EAAT2 interaction by 
      electrophysiological recording of L-Glu-induced current in Xenopus oocytes 
      transfected with EAATs, their chimeras, and single mutants. DHA transiently 
      increased the amplitude of EAAT2 but tended to decrease that of excitatory amino 
      acid transporter subtype 1 (EAAT1), another astrocytic EAAT. Single mutation of 
      leucine (Leu) 434 to alanine (Ala) completely suppressed the augmentation by DHA, 
      while mutation of EAAT1 Ala 435 (corresponding to EAAT2 Leu434) to Leu changed 
      the effect from suppression to augmentation. Other polyunsaturated fatty acids 
      (docosapentaenoic acid, eicosapentaenoic acid, arachidonic acid, and alpha-linolenic 
      acid) similarly augmented the EAAT2 current and suppressed the EAAT1 current. 
      Finally, our docking analysis suggested the most stable docking site is the lipid 
      crevice of EAAT2, in close proximity to the L-Glu and sodium binding sites, 
      suggesting that the DHA/Leu434 interaction might affect the elevator-like slide 
      and/or the shapes of the other binding sites. Collectively, our results highlight 
      a key molecular detail in the DHA-induced regulation of synaptic transmission 
      involving EAATs.
CI  - Copyright (c) 2022 The Authors. Published by Elsevier Inc. All rights reserved.
FAU - Takahashi, Kanako
AU  - Takahashi K
AD  - Laboratory of Neuropharmacology, Division of Pharmacology, National Institute of 
      Health Sciences, Kawasaki, Kanagawa, Japan.
FAU - Chen, Luying
AU  - Chen L
AD  - Laboratory of Organic and Medicinal Chemistry, Graduate School of Pharmaceutical 
      Sciences, The University of Tokyo, Tokyo, Japan.
FAU - Sayama, Misa
AU  - Sayama M
AD  - Laboratory of Organic and Medicinal Chemistry, Graduate School of Pharmaceutical 
      Sciences, The University of Tokyo, Tokyo, Japan.
FAU - Wu, Mian
AU  - Wu M
AD  - Laboratory of Organic and Medicinal Chemistry, Graduate School of Pharmaceutical 
      Sciences, The University of Tokyo, Tokyo, Japan.
FAU - Hayashi, Mariko Kato
AU  - Hayashi MK
AD  - Department of Food Science and Nutrition, Faculty of Food and Health Sciences, 
      Showa Women's University, Tokyo, Japan.
FAU - Irie, Tomohiko
AU  - Irie T
AD  - Laboratory of Neuropharmacology, Division of Pharmacology, National Institute of 
      Health Sciences, Kawasaki, Kanagawa, Japan.
FAU - Ohwada, Tomohiko
AU  - Ohwada T
AD  - Laboratory of Organic and Medicinal Chemistry, Graduate School of Pharmaceutical 
      Sciences, The University of Tokyo, Tokyo, Japan.
FAU - Sato, Kaoru
AU  - Sato K
AD  - Laboratory of Neuropharmacology, Division of Pharmacology, National Institute of 
      Health Sciences, Kawasaki, Kanagawa, Japan. Electronic address: 
      kasato@nihs.go.jp.
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20221209
PL  - United States
TA  - J Biol Chem
JT  - The Journal of biological chemistry
JID - 2985121R
RN  - 25167-62-8 (Docosahexaenoic Acids)
RN  - 0 (Excitatory Amino Acid Transporter 2)
RN  - 3KX376GY7L (Glutamic Acid)
RN  - GMW67QNF9C (Leucine)
SB  - IM
EIN - J Biol Chem. 2023 Jul;299(7):104931. PMID: 37348254
MH  - *Docosahexaenoic Acids/metabolism
MH  - *Excitatory Amino Acid Transporter 2/genetics/metabolism
MH  - Glutamic Acid/metabolism
MH  - Leucine
MH  - *Synaptic Transmission
MH  - Mutation
MH  - *Xenopus laevis/metabolism
PMC - PMC9823230
OTO - NOTNLM
OT  - astrocyte
OT  - electrophysiology
OT  - glutamate
OT  - polyunsaturated fatty acid (PUFA)
OT  - transporter
COIS- Conflicts of interest The authors declare that they have no conflicts of interest 
      with the contents of this article.
EDAT- 2022/12/13 06:00
MHDA- 2023/01/28 06:00
PMCR- 2022/12/09
CRDT- 2022/12/12 19:23
PHST- 2022/04/13 00:00 [received]
PHST- 2022/11/30 00:00 [revised]
PHST- 2022/12/04 00:00 [accepted]
PHST- 2022/12/13 06:00 [pubmed]
PHST- 2023/01/28 06:00 [medline]
PHST- 2022/12/12 19:23 [entrez]
PHST- 2022/12/09 00:00 [pmc-release]
AID - S0021-9258(22)01236-4 [pii]
AID - 102793 [pii]
AID - 10.1016/j.jbc.2022.102793 [doi]
PST - ppublish
SO  - J Biol Chem. 2023 Jan;299(1):102793. doi: 10.1016/j.jbc.2022.102793. Epub 2022 
      Dec 9.