Opioid precursor protein isoform is targeted to the cell nuclei in the human brain.
Biochim Biophys Acta Gen Subj
; 1861(2): 246-255, 2017 Feb.
Article
en En
| MEDLINE
| ID: mdl-27838394
ABSTRACT
BACKGROUND:
Neuropeptide precursors are traditionally viewed as proteins giving rise to small neuropeptide molecules. Prodynorphin (PDYN) is the precursor protein to dynorphins, endogenous ligands for the κ-opioid receptor. Alternative mRNA splicing of neuropeptide genes may regulate cell- and tissue-specific neuropeptide expression and produce novel protein isoforms. We here searched for novel PDYN mRNA and their protein product in the human brain.METHODS:
Novel PDYN transcripts were identified using nested PCR amplification of oligo(dT) selected full-length capped mRNA. Gene expression was analyzed by qRT-PCR, PDYN protein by western blotting and confocal imaging, dynorphin peptides by radioimmunoassay. Neuronal nuclei were isolated using fluorescence-activated nuclei sorting (FANS) from postmortem human striatal tissue. Immunofluorescence staining and confocal microscopy was performed for human caudate nucleus.RESULTS:
Two novel human PDYN mRNA splicing variants were identified. Expression of one of them was confined to the striatum where its levels constituted up to 30% of total PDYN mRNA. This transcript may be translated into ∆SP-PDYN protein lacking 13 N-terminal amino acids, a fragment of signal peptide (SP). ∆SP-PDYN was not processed to mature dynorphins and surprisingly, was targeted to the cell nuclei in a model cellular system. The endogenous PDYN protein was identified in the cell nuclei in human striatum by western blotting of isolated neuronal nuclei, and by confocal imaging. CONCLUSIONS AND GENERALSIGNIFICANCE:
High levels of alternatively spliced ∆SP-PDYN mRNA and nuclear localization of PDYN protein suggests a nuclear function for this isoform of the opioid peptide precursor in human striatum.Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Núcleo Caudado
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Núcleo Celular
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Péptidos Opioides
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Isoformas de Proteínas
Límite:
Adult
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Aged
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Aged80
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Animals
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Biochim Biophys Acta Gen Subj
Año:
2017
Tipo del documento:
Article
País de afiliación:
Ucrania