Use the Following to Answer Questions

Use the following to answer questions
Figure A below shows a restriction map of a rare prokaryotic gene with its direction of transcription indicated by the arrow. Figure B shows the unique restriction sites contained within a plasmid-cloning vector. The blackened region in Figure A represents the amino acid coding sequence of a protein that can be used in humans as a vaccine. The striped region in Figure B is a highly active, constitutive (unregulated) prokaryotic promoter region. Letters indicate the cleavage sites for different restriction enzymes. Known DNA sequences are indicated by short thick lines.
-After trying to isolate and then insert the coding region (Figure
A) under the control of the indicated promoter in the cloning vector (Figure
B), you found that all the transformed bacterial cells contained either one of two smaller portions of the coding region for the gene, and some of the fragments were inserted backward (with regard to reading frame) into the cloning vector. How would you explain these observations?