Compose negative response to send to gallery (6)
I believe the answer is:
notate
'compose negative response' is the definition.
'notate' can be an answer for 'compose' (I've seen this before). I'm not sure about the 'negative response' bit.
'send to gallery' is the wordplay.
'send' becomes 'no' (I can't justify this - if you can you should give a lot more credence to this answer).
'to gallery' becomes 'tate' (Tate Modern, Tate Britain etc).
'no'+'tate'='NOTATE'
'to' is the link.
Can you help me to learn more?
(Other definitions for notate that I've seen before include "Write in system of signs or symbols" , "Compose" , "Write using signs or symbols as in music etc" , "Mark up" , "Put down in writing" .)