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Structure and expression of the rat apolipoprotein E gene.
The Journal of Biological Chemistry
|October 15, 1986
Summary
Researchers isolated and sequenced the rat apolipoprotein E gene, identifying regulatory elements and confirming its functional expression in transfected cells. This provides insights into apolipoprotein E gene regulation and function.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- Apolipoprotein E (ApoE) plays a crucial role in lipid metabolism and transport.
- Understanding the genetic regulation of ApoE is essential for studying related diseases.
Purpose of the Study:
- To isolate and characterize the rat apolipoprotein E gene.
- To identify regulatory sequences within the gene and its flanking regions.
- To assess the functional expression of the cloned rat ApoE gene.
Main Methods:
- Genomic library screening using a cDNA probe.
- DNA sequencing of the gene and flanking regions.
- Analysis of promoter elements (TATA box, Sp1 binding sites).
- Gene transfection into murine L cells and mRNA expression analysis.
- Detection of secreted ApoE protein.
Main Results:
- The complete nucleotide sequence of the rat apolipoprotein E gene, including 5' and 3' flanking regions, was determined.
- Key regulatory elements such as the TATA box and Sp1 binding sites were identified.
- A highly conserved, GC-rich 5' proximal region with potential regulatory function was found.
- The cloned rat ApoE gene was successfully expressed in murine L cells, producing mRNA and secreted protein at levels comparable to rat liver.
Conclusions:
- The rat apolipoprotein E gene possesses regulatory elements in its flanking regions that likely control transcription.
- The conserved 5' region suggests important regulatory mechanisms for ApoE gene expression.
- The successful expression and secretion of rat ApoE in transfected cells validate the cloned gene's functionality.
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