Mouse microsomal triglyceride transfer protein large subunit: cDNA cloning, tissue-specific expression and...

Area of Science:

• Biochemistry
• Genetics
• Molecular Biology

Background:

• Microsomal triglyceride transfer protein (MTP) is vital for lipid transport and apolipoprotein B secretion.
• MTP mutations cause abetalipoproteinemia, a disorder affecting lipid absorption.
• Mice are valuable models for studying lipoprotein metabolism.

Purpose of the Study:

• To clone and sequence mouse MTP cDNA.
• To analyze the sequence identity and conservation of mouse MTP compared to other species.
• To determine the tissue-specific expression and chromosomal localization of the mouse MTP gene.

Main Methods:

• Cloning and sequencing of mouse MTP cDNA.
• DNA-deduced amino acid sequence analysis.
• Northern blot analysis for mRNA expression.
• Southern blot analysis for gene localization using interspecific backcross panels.

Main Results:

• Mouse MTP cDNA was cloned and sequenced, revealing an 894-amino acid protein.
• Mouse MTP shares high sequence identity with hamster (93%), human (86%), and bovine (83%) MTP.
• MTP mRNA is highly expressed in the small intestine and less so in the liver, with no detectable levels in other examined tissues.
• The mouse MTP gene was mapped to the distal region of chromosome 3.
• The C-terminal region of MTP is more conserved across species than the N-terminal region.

Conclusions:

• The characterization of mouse MTP provides a valuable resource for studying MTP function and related diseases.
• Comparative sequence analysis highlights conserved regions of MTP important for its function.
• The expression pattern and gene localization provide insights into MTP's role in lipid metabolism in mice.