Characterization and functional analysis of chicken APOBEC4.

Area of Science:

• Immunology
• Virology
• Genomics

Background:

• APOBEC proteins are crucial for innate and adaptive immunity via deaminase activities.
• Chicken APOBEC1 and APOBEC3 are absent, prompting investigation into chicken APOBEC4 (chA4) functions.
• Understanding chA4 is vital given its potential role in avian health and disease resistance.

Purpose of the Study:

• To identify and characterize chicken APOBEC4 (chA4) mRNA and its functional significance.
• To investigate chA4 expression patterns in response to Newcastle Disease Virus (NDV) infection.
• To evaluate the antiviral potential of chA4 against NDV.

Main Methods:

• Bioinformatics analysis to identify conserved motifs and active sites in chA4.
• Quantitative analysis of chA4 mRNA expression in various chicken tissues and cell lines.
• In vitro and in vivo experiments to assess chA4 expression changes and antiviral activity upon NDV infection.

Main Results:

• Chicken APOBEC4 (chA4) mRNA was identified, revealing a conserved zinc-coordinating motif with active sites.
• chA4 expression was highest in lymphocytes and bursa of Fabricius, and significantly upregulated in immune cells and tissues upon NDV infection.
• Exogenous chA4 expression inhibited NDV replication and reduced viral RNA levels in infected cells.

Conclusions:

• Chicken APOBEC4 (chA4) is a newly identified immune-related gene in chickens.
• chA4 plays a role in the chicken immune system, particularly in antiviral responses against Newcastle Disease Virus.
• chA4 represents a potential target for enhancing avian antiviral immunity.