Queen contributed to cultural channel (6)
I believe the answer is:
artery
'channel' is the definition.
(artery is a kind of channel)
'queen contributed to cultural' is the wordplay.
'queen' becomes 'er' (abbreviation for Elizabeth Regina).
'contributed to' means one lot of letters goes inside another.
'cultural' becomes 'arty'.
'er' put within 'arty' is 'ARTERY'.
(Other definitions for artery that I've seen before include "Important transport route" , "Vessel taking blood from heart" , "M1?" , "Principle channel of circulatory system" , "vital route" .)