The problem with MATE packages I posted yesterday can be solved by preferences file.

Create the file as root, by any text editor, nano for example:
nano /etc/apt/preferences

and past the code:
Package: *
Pin: origin repo.mate-desktop.org
Pin-Priority: 700

Then run:
apt-get update && apt-get dist upgrade

From now, the package manager will be installing and upgrading MATE packages from MATE repository instead of Debian repos.