Complex sentence: The frescoes in the apse date to 1506, executed by Bernardino del Signoraccio: today only the central part, with the the "Father supported by Four Angels", survives.
Split into simpler sentences: The frescoes in the apse date to 1506, executed by Bernardino del Signoraccio. Today only the central part, with the "Father supported by Four Angels", survives.