American journalist, informed and exhausted (4,2)
I believe the answer is:
used up
'exhausted' is the definition.
('use up' can be a synonym of 'exhaust')
'american journalist informed' is the wordplay.
'american' becomes 'US' (United States).
'journalist' becomes 'ed' (short for editor).
'informed' becomes 'up' (being up on a topic means being informed about it).
'us'+'ed'+'up'='USED-UP'
'and' is the link.
(Other definitions for used up that I've seen before include "Consumed completely" , "Exhausted the supply" , "Consumed, finished" , "Spent" .)