My personal opinion on this is that if the domain is rebuilt around the original content and the domain is resubmitted to Google via the webmaster console then there's no reason why the
PR shouldn't return in time.
As others have said, the backlinks are still there and it's those that give the
PR so as long as Google can be shown that the domain has been recreated for genuine purposes. What they can take away they can certainly re-instate as well.
What I'll do is register a domain that had
PR and some quality backlinks (found via
Unwanted-Domain-Names.co.uk), will rehost and rebuild it and I'll see what happens.
I'll report my findings back here.
Phil