A C-terminal motif containing a PKC phosphorylation site regulates γ-Protocadherin-mediated dendrite arborization in the cerebral cortex in vivo.
Dev Neurobiol
; 84(3): 217-235, 2024 Jul.
Article
em En
| MEDLINE
| ID: mdl-38837880
ABSTRACT
The Pcdhg gene cluster encodes 22 γ-Protocadherin (γ-Pcdh) cell adhesion molecules that critically regulate multiple aspects of neural development, including neuronal survival, dendritic and axonal arborization, and synapse formation and maturation. Each γ-Pcdh isoform has unique protein domains-a homophilically interacting extracellular domain and a juxtamembrane cytoplasmic domain-as well as a C-terminal cytoplasmic domain shared by all isoforms. The extent to which isoform-specific versus shared domains regulate distinct γ-Pcdh functions remains incompletely understood. Our previous in vitro studies identified protein kinase C (PKC) phosphorylation of a serine residue within a shared C-terminal motif as a mechanism through which γ-Pcdh promotion of dendrite arborization via myristoylated alanine-rich C-kinase substrate (MARCKS) is abrogated. Here, we used CRISPR/Cas9 genome editing to generate two new mouse lines expressing only non-phosphorylatable γ-Pcdhs, due either to a serine-to-alanine mutation (PcdhgS/A) or to a 15-amino acid C-terminal deletion resulting from insertion of an early stop codon (PcdhgCTD). Both lines are viable and fertile, and the density and maturation of dendritic spines remain unchanged in both PcdhgS/A and PcdhgCTD cortex. Dendrite arborization of cortical pyramidal neurons, however, is significantly increased in both lines, as are levels of active MARCKS. Intriguingly, despite having significantly reduced levels of γ-Pcdh proteins, the PcdhgCTD mutation yields the strongest phenotype, with even heterozygous mutants exhibiting increased arborization. The present study confirms that phosphorylation of a shared C-terminal motif is a key γ-Pcdh negative regulation point and contributes to a converging understanding of γ-Pcdh family function in which distinct roles are played by both individual isoforms and discrete protein domains.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteína Quinase C
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Caderinas
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Córtex Cerebral
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Dendritos
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Proteínas Relacionadas a Caderinas
Limite:
Animals
Idioma:
En
Revista:
Dev Neurobiol
Assunto da revista:
BIOLOGIA
/
NEUROLOGIA
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
Estados Unidos