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Updated: Jun 2, 2026
11:31
Analysis of Protein-protein Interactions and Co-localization Between Components of Gap, Tight, and Adherens Junctions in Murine Mammary Glands
Published on: May 30, 2017
Claudin-18 gene structure, regulation, and expression is evolutionary conserved in mammals
Ozlem Türeci1, Michael Koslowski, Gerd Helftenbein
1Ganymed Pharmaceuticals AG, Freiligrathstr. Mainz, Germany. o.tureci@ganymed.ag
Gene
|May 17, 2011
Summary
Claudin-18 isoform 2 (CLDN18.2) is highly conserved across mammals, exclusively found in gastric cells. This conservation makes multiple mammalian species suitable models for developing CLDN18.2 targeted therapies.
Area of Science:
- Molecular Biology
- Genetics
- Comparative Genomics
Background:
- Claudin-18 isoform 2 (CLDN18.2) is a tight junction protein restricted to gastric cells.
- Understanding its conservation across species is crucial for therapeutic development.
Purpose of the Study:
- To compare the molecular structure and tissue distribution of CLDN18.2 in various mammalian species.
- To assess the phylogenetic conservation of CLDN18.2 and its regulatory elements.
Main Methods:
- Sequence analysis of CLDN18.2 protein and promoter regions.
- RT-PCR and immunohistochemistry to determine tissue expression.
- Comparative analysis across species including mouse, rat, rabbit, dog, monkey, human, and lizard.
Main Results:
- CLDN18.2 protein sequence and promoter regions show high conservation across investigated mammals and lizards.
- CLDN18.2 transcripts and proteins are exclusively expressed in differentiated gastric cells in all species studied.
- Claudin-18 isoform 1 (CLDN18.1) also exhibits homologous gene structure and expression patterns.
Conclusions:
- CLDN18.2 displays significant phylogenetic conservation in structure and gastric-specific expression.
- The high conservation supports the use of multiple mammalian models for CLDN18.2 drug safety testing.
- These findings highlight conserved lineage-specific gene family members and their relevance in drug development.
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