OnMouseDown() is not working in the GUITexture

Follwing module is attached in GUITexture, however there is no reaction in OnMouseDown().
Please help me. I couldn’t find any proper answer in this page.

using UnityEngine;
using System.Collections;

public class SceneMove : MonoBehaviour 
    public string SceneName;

    public void OnMouseDown(){
        print ("LoadLevel");
        Application.LoadLevel( SceneName );		

    void update()

there are no errors in your code, the only thing that it could be is that you are not clicking on a Collider. if you want this to work when ever you click, just put a box taking up the whole screen then turn of its renderer and attach this script to it.