Electron microscope analysis of mouse and rabbit globin and immunoglobulin gene sequences

Area of Science:

• Molecular Biology
• Genetics
• Biochemistry

Background:

• Eukaryotic gene sequences synthesized in vitro are crucial for genetic research.
• Plasmids serve as vectors for inserting and studying foreign DNA.
• Electron microscopy and heteroduplex analysis are key techniques for DNA structural examination.

Purpose of the Study:

• To analyze the structure and integrity of synthesized globin and immunoglobulin gene sequences inserted into plasmids.
• To identify any structural abnormalities at the DNA insertion sites within chimeric plasmids.

Main Methods:

• In vitro synthesis of eukaryotic messenger RNAs (mRNAs) into DNA sequences.
• Insertion of synthesized DNA into plasmid vectors.
• Electron microscopy for visualizing DNA structures.
• Heteroduplex analysis for detecting structural variations and deletions.

Main Results:

• Estimated sizes for inserted DNA sequences: beta rabbit globin (620 bp), alpha and beta mouse globin (620 bp), and alpha rabbit globin (490 bp).
• The immunoglobulin light chain gene sequence measured approximately 830 bases.
• No structural abnormalities were found at most insertion sites.
• A significant 3 kb deletion was observed adjacent to the insertion site of the immunoglobulin light chain gene plasmid.

Conclusions:

• Synthesized globin and immunoglobulin gene sequences can be successfully inserted into plasmids.
• Electron microscopy and heteroduplex analysis are effective for characterizing chimeric plasmids.
• Potential structural alterations, such as deletions, can occur during plasmid construction, particularly with larger gene inserts.