Orange-spotted grouper Epinephelus coioides Tak1: molecular identification, expression analysis and functional study

Area of Science:

• Aquatic immunology
• Molecular biology
• Fish disease resistance

Background:

• The Tak1 gene plays a role in cellular signaling pathways.
• Understanding fish immune responses is crucial for aquaculture.
• The orange-spotted grouper (Epinephelus coioides) is an important aquaculture species.

Purpose of the Study:

• To clone and characterize the complementary (c)DNA of orange-spotted grouper Tak1 (Ectak1).
• To investigate the expression pattern and function of Ectak1 in response to parasitic infection.
• To elucidate Ectak1's role in the NF-κB signaling pathway.

Main Methods:

• Complementary (c)DNA cloning and sequencing of Ectak1.
• Quantitative expression analysis of ectak1 transcripts in various tissues.
• Intracellular localization studies using Ectak1.
• Luciferase reporter assays to assess NF-κB activity.

Main Results:

• The ectak1 gene encodes a protein with conserved kinase and coiled-coil domains.
• Ectak1 transcripts were widely expressed but downregulated at infection sites.
• Ectak1 localized to the cytoplasm and inhibited NF-κB activation.
• Ectak1 impairs NF-κB activity induced by toll-like receptor (TLR) signaling molecules.

Conclusions:

• Ectak1 is a functional Tak1 protein in orange-spotted grouper.
• Ectak1 plays a role in modulating the host immune response.
• Ectak1 may be involved in host defense against parasitic infections by regulating NF-κB signaling.