The program MEGA does not output nested parenthesis style tree descriptions that TreeView normally requires. However, it is possible to get MEGA to output a tree description that TreeView can read. The Appendices to the MEGA manual contain a description of how to produce a tree file that will look something like this:
NB0 3 1 A 2 B 3 C 4 1 2 0.005 0.002 5 3 4 0.002 0.001 0
TreeView will read this tree format. Note that TreeView will not read the text-based tree drawings produced by MEGA, such as:
