Gui button and iventory problem

I try to do a gui button for my inventory. And there's a problem after click sound play but description texture don't show :(

Any ideas why?

 ////////// item //////////
 
 
 var inventoryIcon:Texture2D;
 var descriptionTex:Texture2D;
 var obj:GameObject;
 public var info:AudioClip;
 public var nul:AudioClip;
 function OnMouseDown(){
     if(!collider.isTrigger){
     
         var playersinv=FindObjectOfType(InventoryJS);    
         playersinv.AddItem(this.transform);    
         collider.isTrigger = true;    
     }else{
     obj.audio.PlayOneShot(nul);
     
     }
 
     }
 
 
 ///////////Inventory///////////
 
 
 var Contents:Transform[];
 
 function AddItem(Item:Transform){
     var newContents=new Array(Contents);
     newContents.Add(Item);
     Debug.Log(Item.name+" Has been added to inventroy");
     Contents=newContents.ToBuiltin(Transform);
 }
 
 
 ///////////Gui/////////////
 
 
 private var windowPosition:Vector2=Vector2(0,0);
 private var windowSize:Vector2=Vector2(1000.0,1000.0);
 var itemIconSize:Vector2=Vector2(100.0,100.0);
 var back:Texture;
 private var pressed:boolean=false;
 private var visible:boolean=false;
 private var lastTooltip :String = "";
 var updateListDelay=1.0;
 var UpdatedList:Transform[];
 var lastUpdate = 1.0;
 var associatedInventory:InventoryJS;
 var person:CharacterController;
 private var counter = 0;
 
 
 function Update () {
  if(Input.GetKeyDown(KeyCode.Escape)){
      if(pressed == false){
      Screen.lockCursor = false;
      Screen.showCursor = true;
       GetComponent(MouseLook).enabled = false;
     person.GetComponent(MouseLook).enabled = false;
     Crosshair.on = false;
   pressed = true;
   Time.timeScale = 0;
   visible = true;
    }else{
       Screen.lockCursor = true;
       Screen.showCursor = false;
       GetComponent(MouseLook).enabled = true;
     person.GetComponent(MouseLook).enabled  = true;
     Crosshair.on = true;
        visible = false;
     pressed = false;
     Time.timeScale = 1.0;
   }
  }
  }
 function UpdateInventoryList(){
     UpdatedList=associatedInventory.Contents;
 }
 function OnGUI(){
         if(visible&&pressed){
     var currentX=windowPosition.x;
     var currentY=windowPosition.y;
     GUI.DrawTexture(Rect(0,0,Screen.width,Screen.height),back,ScaleMode.StretchToFill);
     for(var i:Transform in UpdatedList){
     var item=i.GetComponent.<ItemJS>();
         if(GUI.Button(Rect(currentX ,currentY,itemIconSize.x,itemIconSize.y),GUIContent (item.inventoryIcon, "tooltip"))){
             GUI.DrawTexture(Rect(Screen.width/2,Screen.height/2,item.descriptionTex.x,item.descriptionTex.y),item.descriptionTex);
             item.audio.PlayOneShot(item.sound);
             lastUpdate=0.0;
         }
         currentX+=itemIconSize.x;
         if(currentX+itemIconSize.x>windowPosition.x+windowSize.x){
             currentX=windowPosition.x;
             currentY+=itemIconSize.y;
             if(currentY+itemIconSize.y>windowPosition.y+windowSize.y){
                 return;
                 }
             }
         }
         
         if(GUI.Button(Rect(0, Screen.height/2+(Screen.height/2-30), Screen.width/2-1, 29), "Quit Game")){
         Application.Quit();
         }
         if(GUI.Button(Rect(Screen.width/2, Screen.height/2+(Screen.height/2-30), Screen.width/2-1, 29), "Back To Main Menu")){
         Application.LoadLevel ("menu");
         }
         
         
         
     }
 }
 
 
 function FixedUpdate(){
     if(Time.time>lastUpdate){
         lastUpdate=Time.time+updateListDelay;
         UpdateInventoryList();
     }
 }