Molecular cloning

Area of Science:

• * Molecular Biology
• * Immunology
• * Fish Biology

Background:

• * Transcription factor c-Jun, a component of the AP-1 complex, is crucial for vertebrate immune responses.
• * Pathogen-induced expression of c-Jun highlights its regulatory role in immunity.

Purpose of the Study:

• * To clone and characterize the c-Jun gene from large yellow croaker (Larimichthys crocea), named Lcc-Jun.
• * To investigate the expression patterns and immune-inducible nature of Lcc-Jun.
• * To explore the role of Lcc-Jun in regulating T helper cell responses.

Main Methods:

• * Cloning of the full-length Lcc-Jun cDNA.
• * Analysis of Lcc-Jun protein domains (transactivation, DNA binding, Leucine zipper).
• * Gene expression analysis in various tissues and immune cells (PKL, PKM, PKG) upon stimulation with poly (I:C) and LPS.
• * Overexpression studies in primary head kidney leukocytes (PKL) to assess effects on cytokine and transcription factor expression.

Main Results:

• * Lcc-Jun cDNA encodes a 327-amino acid protein with conserved c-Jun domains.
• * Lcc-Jun is constitutively expressed in multiple tissues, with higher levels in blood, heart, and head kidney.
• * Lcc-Jun transcripts are induced by poly (I:C) and LPS in immune organs and cells.
• * Overexpression of Lcc-Jun promotes the expression of Th1 and Th2 cytokines and transcription factors.

Conclusions:

• * Lcc-Jun plays a significant role in the immune response of large yellow croaker.
• * Lcc-Jun is involved in the regulation of both T helper 1 and T helper 2 cell differentiation.
• * c-Jun-mediated signaling pathways are important for immune modulation in teleost fish.