PMID- 36347955
OWN - NLM
STAT- MEDLINE
DCOM- 20221116
LR  - 20230105
IS  - 2045-2322 (Electronic)
IS  - 2045-2322 (Linking)
VI  - 12
IP  - 1
DP  - 2022 Nov 8
TI  - A link between agrin signalling and Ca(v)3.2 at the neuromuscular junction in 
      spinal muscular atrophy.
PG  - 18960
LID - 10.1038/s41598-022-23703-x [doi]
LID - 18960
AB  - SMN protein deficiency causes motoneuron disease spinal muscular atrophy (SMA). 
      SMN-based therapies improve patient motor symptoms to variable degrees. An early 
      hallmark of SMA is the perturbation of the neuromuscular junction (NMJ), a 
      synapse between a motoneuron and muscle cell. NMJ formation depends on 
      acetylcholine receptor (AChR) clustering triggered by agrin and its co-receptors 
      lipoprotein receptor-related protein 4 (LRP4) and transmembrane muscle-specific 
      kinase (MuSK) signalling pathway. We have previously shown that flunarizine 
      improves NMJs in SMA model mice, but the mechanisms remain elusive. We show here 
      that flunarizine promotes AChR clustering in cell-autonomous, dose- and 
      agrin-dependent manners in C2C12 myotubes. This is associated with an increase in 
      protein levels of LRP4, integrin-beta-1 and alpha-dystroglycan, three agrin 
      co-receptors. Furthermore, flunarizine enhances MuSK interaction with 
      integrin-beta-1 and phosphotyrosines. Moreover, the drug acts on the expression 
      and splicing of Agrn and Cacna1h genes in a muscle-specific manner. We reveal 
      that the Cacna1h encoded protein Cav3.2 closely associates in vitro with the 
      agrin co-receptor LRP4. In vivo, it is enriched nearby NMJs during neonatal 
      development and the drug increases this immunolabelling in SMA muscles. Thus, 
      flunarizine modulates key players of the NMJ and identifies Ca(v)3.2 as a new 
      protein involved in the NMJ biology.
CI  - (c) 2022. The Author(s).
FAU - Delers, Perrine
AU  - Delers P
AD  - T3S, INSERM, Universite Paris Cite, 75006, Paris, France.
FAU - Sapaly, Delphine
AU  - Sapaly D
AD  - T3S, INSERM, Universite Paris Cite, 75006, Paris, France.
FAU - Salman, Badih
AU  - Salman B
AD  - T3S, INSERM, Universite Paris Cite, 75006, Paris, France.
FAU - De Waard, Stephan
AU  - De Waard S
AD  - L'institut du Thorax, INSERM, CNRS, Nantes Universite, 44000, Nantes, France.
FAU - De Waard, Michel
AU  - De Waard M
AD  - L'institut du Thorax, INSERM, CNRS, Nantes Universite, 44000, Nantes, France.
FAU - Lefebvre, Suzie
AU  - Lefebvre S
AD  - T3S, INSERM, Universite Paris Cite, 75006, Paris, France. 
      suzie.lefebvre@inserm.fr.
LA  - eng
GR  - ANR-21-CE17-0039-01/Agence Nationale de la Recherche/
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20221108
PL  - England
TA  - Sci Rep
JT  - Scientific reports
JID - 101563288
RN  - 0 (Agrin)
RN  - R7PLA2DM0J (Flunarizine)
RN  - 0 (Integrins)
RN  - EC 2.7.10.1 (Receptor Protein-Tyrosine Kinases)
RN  - 0 (Receptors, Cholinergic)
RN  - 0 (Cacna1h protein, mouse)
SB  - IM
MH  - Animals
MH  - Mice
MH  - *Agrin/genetics/metabolism
MH  - Flunarizine
MH  - Integrins/metabolism
MH  - *Muscular Atrophy, Spinal/metabolism
MH  - Neuromuscular Junction/metabolism
MH  - Receptor Protein-Tyrosine Kinases/metabolism
MH  - Receptors, Cholinergic/genetics/metabolism
PMC - PMC9643518
COIS- The authors declare no competing interests.
EDAT- 2022/11/09 06:00
MHDA- 2022/11/11 06:00
PMCR- 2022/11/08
CRDT- 2022/11/08 23:29
PHST- 2022/01/20 00:00 [received]
PHST- 2022/11/03 00:00 [accepted]
PHST- 2022/11/08 23:29 [entrez]
PHST- 2022/11/09 06:00 [pubmed]
PHST- 2022/11/11 06:00 [medline]
PHST- 2022/11/08 00:00 [pmc-release]
AID - 10.1038/s41598-022-23703-x [pii]
AID - 23703 [pii]
AID - 10.1038/s41598-022-23703-x [doi]
PST - epublish
SO  - Sci Rep. 2022 Nov 8;12(1):18960. doi: 10.1038/s41598-022-23703-x.