Depends - is yours a basic 1.0l model, SR, Super S, GX, Si, etc. It varies from model to model, normally central locking was only fitted to higher spec models
I'm not 100%. I think it was an optional extra on the lower models, whereas it was fitted as standard to higher spec models. I've seen a lot of 1.0l Micras with central locking (including on the most basic models), and some without. So if yours might not have had it fitted