No...it is also available on other aftermarket stereos, just depends if the head unit is capable of receiving the signal. But if you mean is it available on the Non-Bose system of the Murano I am not sure since I have the Bose.
I thought I remember someone with non bose saying they had rds still, but not sure. You may have it but the stations in your area may not broadcast a signal. Even where I am only some stations broadcast and even then they only do it at certain times.