Amino acid sequence of rabbit apolipoprotein E

Area of Science:

• Biochemistry
• Molecular Biology
• Proteomics

Background:

• Apolipoprotein E (apoE) plays a crucial role in lipid metabolism and transport.
• Understanding the precise amino acid sequence of apoE is essential for studying its function and structure.
• Rabbit apoE serves as a model for studying human apoE due to potential similarities.

Purpose of the Study:

• To determine the complete amino acid sequence of rabbit apolipoprotein E (apoE).
• To compare the determined rabbit apoE sequence with the sequence inferred from cDNA.
• To assess the homology between rabbit and human apoE sequences for potential in vitro studies.

Main Methods:

• Protein cleavage using cyanogen bromide, endoproteinase AspN, and Staphylococcus aureus V8 protease.
• N-terminal and C-terminal residue identification through sequence analysis.
• Amino acid sequencing of 294 residues to determine molecular weight and sequence homology.

Main Results:

• The complete amino acid sequence of rabbit apoE was elucidated, comprising 294 residues with a molecular weight of 33,684 Da.
• The determined protein sequence corrected discrepancies found in the cDNA-inferred sequence.
• Rabbit apoE exhibits 80% homology with human apoE, a higher degree than previously inferred from cDNA.

Conclusions:

• The high amino acid sequence homology between rabbit and human apoE suggests similar physiological properties.
• Rabbit apoE is a suitable model for in vitro studies relevant to human apoE, overcoming limitations of human protein availability.