Is it possible to freeze/make read only description pane in User Story. Owner should only have edit rights and read only to other users?
The permission model is for projects or team. This means that users get their permission levels within their project/team (such as editor/viewer). That permissions applies to all artifacts including all their fields for that project/team.
Our current permission model isn't granular to the fields. There isn't a way to associate levels of permissions to specific fields or even specific artifacts. This will be a good enhancement request and you should be encouraged to post it.
There isn't a way to dynamically adjust the artifact's permission differently to owners vs. others. As said, it's statically mapped between a user and each project/team.
Let us know if that helped.