Dog turning up, sure to be barking (6)
I believe the answer is:
pursue
'dog' is the definition.
(thesaurus)
'turning up sure to be barking' is the wordplay.
'turning' is a reversal indicator.
'to be barking' indicates anagramming the letters (UK slang for mad).
'up' reversed gives 'pu'.
'sure' anagrammed gives 'rsue'.
'pu'+'rsue'='PURSUE'
(Other definitions for pursue that I've seen before include "Engage in or chase after" , "Give chase" , "Search for" , "Follow, chase" , "Chase, run after" .)