Groups and roles for back end

Groups for back end
Hi all,
Would love some advice for how to accomplish the following need:

For a WordPress blog,
users must be divided into groups.
Each user will be able to see only the post he wrote but an editor will be able to edit and see the post of his group (in the admin side, not the front side).

Other Needs:
A user will be able to write but not publish.
The editor won’t be able to publish, on;y top level admin.
If a user or an editor will edit the post after it was published the top admin will be notified and will be able to approve.

Any idea on which plugins can do those things?!
Many Thanks