One in gallery tour car on the move (7)
I believe the answer is:
curator
'one in gallery' is the definition.
(I know that curators often work in galleries)
'tour car on the move' is the wordplay.
'on the move' indicates an anagram.
'tour'+'car'='tourcar'
'tourcar' is an anagram of 'CURATOR'.
(Other definitions for curator that I've seen before include "Person in charge of a museum" , "man in the museum?" , "Museum custodian" , "Custodian - caretaker" , "Museum officer" .)