Extra studies hold up government-appointed 'expert' (4)
I believe the answer is:
tsar
'expert' is the definition.
(I know that tsar is a type of Monarch)
'extra studies hold up' is the wordplay.
'hold' indicates the answer is hidden within the clue (I've seen 'holds' mean this).
'up' says the letters should be written backwards (in down clue: letters go upwards).
'rast' can be found hidden inside 'extra studies'.
'rast' backwards is 'TSAR'.
'government-appointed' acts as a link.
This may not be correct. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for tsar that I've seen before include "Nicholas II, say" , "Old Russian 22" , "Tyrant" , "Nicholas II was the last" , "Russian ruler (S, not Z)" .)