Fine-mapping resolves Eae23 into two QTLs and implicates ZEB1 as a candidate gene regulating experimental...

Area of Science:

• Immunogenetics
• Neuroimmunology
• Genetics of Autoimmune Diseases

Background:

• Investigating genetic mechanisms of multiple sclerosis (MS) through experimental autoimmune encephalomyelitis (EAE) in rats.
• Focus on Eae23, a quantitative trait locus (QTL) previously identified to regulate EAE.
• Aim to identify specific genes within the Eae23 region contributing to EAE susceptibility or resistance.

Purpose of the Study:

• To resolve the Eae23 QTL into finer genetic loci.
• To identify candidate genes responsible for regulating EAE.
• To investigate the role of ZEB1 splice variants in EAE pathogenesis.

Main Methods:

• High-resolution quantitative trait loci (QTL) analysis in an advanced intercross line (AIL).
• Development of a congenic strain to validate QTL effects.
• Exon array analysis to assess gene expression in parental strains.
• Analysis of ZEB1 splice variant expression in lymphoid tissues.

Main Results:

• Eae23 was resolved into two independent QTLs, Eae23a and Eae23b.
• PVG alleles within Eae23 conferred significant protection from EAE and reduced central nervous system (CNS) inflammation and demyelination.
• Congenic rats showed increased Foxp3(+) cells in the CNS.
• Lower expression of ZEB1 exon 4 (specific to Zfhep1) and differential expression of ZEB1 splice variants (Zfhep1, Zfhep2) were observed.
• Down-regulation of Zfhep1 and up-regulation of Zfhep2 correlated with EAE severity and higher IL2 levels.

Conclusions:

• The balance of ZEB1 splice variants may play a crucial role in regulating EAE.
• Further research into ZEB1 and its splice variants could reveal novel pathways in MS pathogenesis and inflammation.