Is it possible to change value on base class when the same field gets changed on it's derived class

Question

I'm using Unity here. My question is, is it possible to change value on base class when the same field gets changed on it's derived class? and vice-versa

I will give an example to make it clear:

public class BaseClass : MonoBehaviour{
    public int x;
}

public class DerivedClass : BaseClass{
    //-------------
}

public class AnotherClass : MonoBehaviour{
    GameObject player = Instantiate(playerModel) as GameObject;  //Assume playerModel is refrenced or something

    DerivedClass example = player.GetComponent<DerivedClass>();

    example.x = 5;
}

In this case player.GetCompenent<DerivedClass >().x will print 5, but player.GetCompenent<BaseClass >().x will print 0. Is there a way to have BaseClass X equal to 5? Without directly setting it to 5