Circadian clock components Bmal1 and Clock1 regulate tlr9 gene expression in the Japanese medaka (Oryzias latipes).
Fish Shellfish Immunol
; 105: 438-445, 2020 Oct.
Article
em En
| MEDLINE
| ID: mdl-32653586
ABSTRACT
Currently, circadian regulation of immune molecules in lower vertebrates, particularly, diurnal oscillation in the immune status of a fish, is not well understood. In this study, the diurnal oscillation of toll-like receptor (Tlr) 9, which plays a role in pathogen recognition, was investigated in the Japanese medaka fish (Oryzias latipes). We confirmed the expression of tlr9 and clock genes (bmal1 and clock1) in the central and peripheral tissues of medaka. These genes were expressed in a diurnal manner in medaka acclimated to a 12-h12-h light-dark (1212 LD) cycle. In addition, increased tlr9 expression was detected in medaka embryo cells (OLHdrR-e3) overexpressing both bmal1 and clock1 genes; however, this result was not obtained when only one or neither of the genes was overexpressed. This suggests that the increase in expression was mediated by the Bmal1 and Clock1 proteins together. In vitro stimulation of the head kidney with CpG-oligodeoxynucleotides (CpG-ODNs) at different zeitgeber times (ZTs; ZT0 = light on, ZT12 = light off) affected the degree of tlr9 gene expression, showing high and low responsiveness to CpG-ODN stimulation at ZT6/10 and ZT18/22, respectively. Similarly, bacterial infection at different ZT points induced a difference in the expression of Tlr9 signaling pathway-related genes (tlr9 and myd88). These results suggested that fish tlr9 exhibits diurnal oscillation, which is regulated by clock proteins, and its responsiveness to immune-stimulation/pathogen infection depends on the time of the day.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oryzias
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Regulação da Expressão Gênica
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Proteínas de Peixes
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Proteínas de Peixe-Zebra
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Proteínas de Ligação a DNA
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Receptor Toll-Like 9
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Fatores de Transcrição ARNTL
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Relógios Circadianos
Limite:
Animals
Idioma:
En
Revista:
Fish Shellfish Immunol
Assunto da revista:
BIOLOGIA
/
MEDICINA VETERINARIA
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Japão