It transmits news about currency (6)
I believe the answer is:
neuron
'it transmits' is the definition.
The definition suggests a singular noun which matches the answer.
'news about currency' is the wordplay.
'news' becomes 'nn' (n is common abbrev for new, news can be plural).
'about' indicates putting letters inside.
'currency' becomes 'euro' (currency of the Eurozone).
'nn' going around 'euro' is 'NEURON'.
Can you help me to learn more?
(Other definitions for neuron that I've seen before include "Conductor" , "Cell that conducts nerve impulses" , "Part of one's nervous system" , "Impulsive thing" , "that makes for nervous transmission" .)