ZFIN ID: ZDB-PUB-180402-1
Circadian genes period1b and period2 differentially regulate inflammatory responses in zebrafish
Ren, D.L., Zhang, J.L., Yang, L.Q., Wang, X.B., Wang, Z.Y., Huang, D.F., Tian, C., Hu, B.
Date: 2018
Source: Fish & shellfish immunology   77: 139-146 (Journal)
Registered Authors: Hu, Bing
Keywords: Circadian clock, Cytokines, Neutrophil migration, per1b, per2
MeSH Terms:
  • Animals
  • Circadian Rhythm/immunology*
  • Eye Proteins/genetics*
  • Eye Proteins/immunology
  • Gene Expression Regulation/immunology*
  • Inflammation/genetics*
  • Inflammation/immunology
  • Period Circadian Proteins/genetics*
  • Period Circadian Proteins/immunology
  • Zebrafish/genetics*
  • Zebrafish/immunology*
  • Zebrafish/injuries
  • Zebrafish Proteins/genetics*
  • Zebrafish Proteins/immunology
PubMed: 29605504 Full text @ Fish Shellfish Immunol.
The circadian clock has been shown to regulate various immune processes in different animals. Our previous report demonstrated that the innate immune responses in zebrafish show significant rhythmicity that could be regulated by melatonin. Here, we used diurnal zebrafish to determine the role of circadian genes in the inflammatory responses. Our results indicate that circadian genes exhibit rhythmic oscillations in zebrafish leukocytes, and mutations of the clock genes period1b (per1b) and period2 (per2) considerably affect these oscillations. Using a wounded zebrafish inflammation model, we found that under constant dark conditions (DD), the expression of pro-inflammatory cytokines is significantly downregulated in per1b gene mutant zebrafish and significantly upregulated in the per2 gene mutant zebrafish. Furthermore, using real-time imaging technology, we found that the per1b gene markedly disturbs the rhythmic recruitment of neutrophils toward the injury, whereas the per2 gene does not show a significant effect. Taken together, our results reveal differential functions of the circadian genes per1b and per2 in the inflammatory responses, serving as evidence that circadian rhythms play a vital role in immune processes.