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Characterization of Membrane Transporters by Heterologous Expression in E. coli and Production of Membrane Vesicles
Published on: December 31, 2019
Characterization of a murine high-affinity thiamine transporter, Slc19a2
J C Fleming1, M P Steinkamp, R Kawatsuji
1Division of Hematology, Children's Hospital, Boston, Massachusetts 02115, USA.
Molecular Genetics and Metabolism
|October 11, 2001
Summary
Thiamine transport is crucial for multiple organ systems. This study characterizes the murine Slc19a2 thiamine transporter, revealing its role in erythropoietic, auditory, and glucose homeostasis systems.
Area of Science:
- Genetics and Molecular Biology
- Physiology
- Biochemistry
Background:
- Thiamine-responsive megaloblastic anemia with deafness and diabetes (TRMA) is a rare genetic disorder.
- TRMA is caused by mutations in the SLC19A2 gene, which encodes a thiamine transporter.
- The role of SLC19A2-mediated thiamine transport in organ system development is not fully understood.
Purpose of the Study:
- To investigate the function and distribution of the thiamine transporter.
- To characterize the murine Slc19a2 gene and protein.
- To explore the role of thiamine transport in erythropoiesis, hearing, and glucose homeostasis.
Main Methods:
- Cloning and characterization of the murine Slc19a2 locus.
- Transient expression of Slc19a2 in HEK293T cells for uptake studies.
- Western blot analysis and immunohistochemistry of mouse tissues.
Main Results:
- Murine Slc19a2 is a 498 amino acid protein with 12 predicted transmembrane domains, structurally similar to its human homolog.
- Slc19a2 expression in HEK293T cells confirmed its function as a thiamine transporter.
- Slc19a2 protein is widely distributed in mouse tissues, localized to cell surfaces and intracellularly, particularly in the cochlea, small intestine, and pancreas.
Conclusions:
- The Slc19a2 gene and protein are structurally conserved between mice and humans.
- Slc19a2 functions as a high-affinity thiamine transporter.
- The distribution of Slc19a2 suggests its critical role in the development and maintenance of auditory, erythropoietic, and glucose homeostasis systems.
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