What does it mean to "nucleate multi-protein complexes"? I am reading an article about the mTOR signalling pathway and I have come across the following: > mTOR nucleates at least two distinct multi-protein complexes, mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2). I am not sure what is meant by "mTOR nucleates 2 multi-protein complexes". From the paper, I understand that mTOR is a component of the mTORC1 and mTORC2 complexes. I have read the definition of 'nucleate' online and it means to either "to form into a cluster" or "to act as a nucleus for". However in the context of this article, I am not clear about what is meant by "nucleates" in the above statement. Any insights are appreciated.

Here nucleation has a rather physical meaning. mTOR acts as the starting assembly point of the complex.