Took me a moment to set this up, i am ill at home currently and not really on my best game.
The attached scene comes with two assets, a nodal material and a node asset that is used within the material.
If you load it you can see three materials and three cubes. All materials are identical in their setup, the only difference is in which version of the node asset they use. I created the node asset with one checkerboard color exposed as a parameter and the other defined within the asset. Version 1.0 uses a different "hardcoded" color than version 1.1.
One of the materials (and the version in the asset browser) always uses the latest version of the asset, so if you edit the asset and save a new version (1.2, 1.3, ...) that one will be used.
This allows you to have a basic material definition that you can globaly update at any time, regardless how many instances of the nodal asset are used in any number of materials. At the same time you can have individual variations of it, where the exposed parameters keep their values even if the asset is updated.
I think, while not the most straight forward method, this can allow for pretty powerful workflows. Imagine creating simple placeholder materials where you only define some color at the start and later flesh them out without ever having to go through your material assignments again.
Node Material with Asset 01.c4d