Show to be in charge in the department (6)
I believe the answer is:
depict
'show' is the definition.
(to depict is to show or portray)
'in charge in the department' is the wordplay.
'in charge' becomes 'ic' (abbreviation for 'in charge').
'in the' indicates putting letters inside.
'department' becomes 'dept'.
'ic' put into 'dept' is 'DEPICT'.
'to be' is the link.
(Other definitions for depict that I've seen before include "Give a description of" , "Show by drawing" , "Sketch or describe" , "Show, illustrate" , "Represent in drawing or painting" .)