Update Panel with Tab control not displaying the controls

Hi,
I have a Tab control which contains two tabs each with a grid.
I have a button say "Go" outside of Tab control within Update Panel say "UpdatePanel1".

Now i have put update panel for each grid in the tab control say "UpdGrid1" and "UpdGird2". And i have set AsynPostbackTrigger for the "Go" button for both "UpdGrid1" and "UpdGrid2".
In "Go" button click event i am loading the grids and binding.

But the gird is not visible after putting using update panel as i specified above.

How should i make this work?

Regards
Gilli