Thank you for participating here @psychassist! It's most accurate to say that gene expression is part of LTP. However, in the 2-receptor mechanism from my article, the NMDA receptor activation would initiate a chain of reactions leading to gene expression of proteins which then act to facilitate and make more permanent this LTP event. So, the initial "receptor-stage" LTP event effects gene expression, and gene expression effects the duration and magnitude of LTP. I hope that makes sense :)