Pope Francis is keeping in place the German prelate who lead the crackdown on U.S. nuns and who also helps craft the Catholic Church's sex-abuse response.

After six months on the job, Francis made several key appointments Saturday in the Vatican's curia, or bureaucracy.

Francis renewed Archbishop Gerhard Mueller in the powerful role of prefect of the Congregation for the Doctrine of the Faith. Mueller, originally appointed by Benedict XVI, directs the Holy See's crackdown on nuns suspected of undermining Catholic teaching on the priesthood and homosexuality. His office also shapes policy dealing with clergy who sexually abuse minors.

The pope replaced an Italian cardinal with an Italian prelate as head of the clergy department, another crucial office as the worldwide Roman Catholic Church grapples with a priest shortage.