Cut pins up! (4)
I believe the answer is:
snip
'cut' is the definition.
(snip is a kind of cut)
'pins up' is the wordplay.
'up' says the letters should be written backwards (in down clue: letters go upwards).
'pins' reversed gives 'SNIP'.
(Other definitions for snip that I've seen before include "vasectomy?" , "Surprisingly cheap item" , "Bargain (coll)" , "Cut - price bargain" , "Cut with scissors - bargain" .)