How can I designate part of a feature on a nucleotide sequence as a segment?
Select the Feature Segment Region

Select the DNA sequence region that will be labeled with a feature segment.
Create a Feature Segment

To create a feature segment, click Features → Create Feature Segment... .
Name the Segment

Type the segment name if desired.
Choose the Segment Color

Choose a different color for the segment if desired.
View the Segment

Click OK to see the segmented feature.