Do you mean a key as in

Key to table below:

an Annapolis

bl Baltimore

If that is what you are talking about then no, the key does not need the dot locator in front of it.

If you define a symbol or a typeform, such as

In the paragraph below [dots 4, 3456, 2] represents a highlighted word

Then yes, a dot locator would be required before that symbol. NOTE: I could not get the font to show the braille so I put dot numbers in.

Cindi