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Updated: Jun 10, 2026
08:58
Characterization of Glycoproteins with the Immunoglobulin Fold by X-Ray Crystallography and Biophysical Techniques
Published on: July 5, 2018
Isoforms, expression, glycosylation, and tissue distribution of CTL2/SLC44A2
P K Kommareddi1, T S Nair, L V Thang
1Kresge Hearing Research Institute, Department of Otolaryngology/Head and Neck Surgery, The University of Michigan, 1150 West Medical Center Drive, Room 5311 Medical Science I, Ann Arbor, MI 48109-5516, USA.
The Protein Journal
|July 29, 2010
Summary
Researchers identified two new isoforms of the solute carrier protein CTL2/SLC44A2 (CTL2 P1 and CTL2 P2). These isoforms have different tissue expression and glycosylation patterns, impacting their function and potential role in autoimmune diseases.
Area of Science:
- Biochemistry
- Molecular Biology
- Immunology
Background:
- Antibodies to CTL2/SLC44A2 are linked to hearing loss and transfusion-related acute lung injury.
- Understanding CTL2/SLC44A2 isoforms is crucial due to the severe consequences of anti-CTL2/SLC44A2 antibodies.
Purpose of the Study:
- To clone and characterize novel isoforms of CTL2/SLC44A2.
- To investigate the tissue-specific expression, posttranslational modifications, and functional differences of CTL2/SLC44A2 isoforms.
Main Methods:
- Cloning of a novel CTL2/SLC44A2 isoform (CTL2 P1) from the inner ear.
- Assessment of isoform expression, posttranslational modifications, and cellular localization using HEK293 cells.
- Functional analysis of choline transport activity via heterologous expression in X. laevis oocytes.
Main Results:
- Identified two CTL2/SLC44A2 isoforms (CTL2 P1 and CTL2 P2) with distinct amino acid sequences in their N-termini.
- Observed variable expression and differing glycosylation patterns of P1 and P2 isoforms across multiple tissues.
- Demonstrated that human CTL2-P1 does not transport choline, whereas human CTL2-P2 exhibits choline transport activity.
Conclusions:
- The study identified and characterized novel CTL2/SLC44A2 isoforms with distinct properties.
- Tissue-specific expression and modifications of CTL2/SLC44A2 isoforms suggest varied functional roles.
- The differential choline transport activity of CTL2-P1 and CTL2-P2 may have implications for understanding SLC44A2-related pathologies.
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