Artist brought up in Philadelphia (4)
I believe the answer is:
dali
'artist' is the definition.
(Salvador Dali)
'up in philadelphia' is the wordplay.
'up' says the letters should be written in reverse (in down clue: letters go upwards).
'in' indicates the answer is hidden within the clue.
'ilad' is hidden in the letters of 'philadelphia'.
'ilad' backwards is 'DALI'.
'brought' acts as a link.
(Other definitions for dali that I've seen before include "Controversial painter" , "Salvador . . . . was great Spanish surrealist painter" , "Surrealist Spanish painter, d. 1989" , "Salvador -, twentieth century artist" , "Salvador among artists" .)