How to display and update data in an editable grid from 2 datatables?

I have a mashup called Mashup1 and it contains Datatable1 and an Editable Grid1. All the changes made in Grid1 is Saved in Datatable1. I also Have another Mashup called Mashup2 and it contains Datatable2 and an Editable Grid2. All the Changes made to Grid2 is saved in Datatable2. Now here is my Problem.

• I wanted to Display row4 from Datatable1 in Editable Grid2. 
• Changes made to row4 from Editable Grid2 should also be reflected in Datatable1.

Thanks in advance. 🙂