A minor 12 bar blues example 

A minor 12 bar blues example
Am7 / / / Am7 / / / Am7 / / / Am7 / / /
Dm7 / / / Dm7 / / / Am7 / / / Am7 / / /
Em7 / / / Dm7 / / / Am7 / / / E7#9 / / /
I incorrectly call the E7#9 “Eadd9”. Both work. E7add#9 works better to my ears.
Use A minor pentatonic over any chord. Use D minor pentatonic over Dm7. Use E minor pentatonic over Em7.
Minor Pentatonic = 1-b3-4-5-b7
A minor pentatonic = A-C-D-E-G
add the flat 5th =Eb for a bluesy touch