Wine producer in different vein (4)
I believe the answer is:
vine
'wine producer' is the definition.
'different vein' is the wordplay.
'different' is an anagram indicator (letters placed in a different order).
'vein' anagrammed gives 'VINE'.
'in' acts as a link.
(Other definitions for vine that I've seen before include "Woody-stemmed climber" , "On which grapes grow" , "Source of the grape" , "Bearer of grape" , "Climbing fruiting plant" .)