message-yank-prefix

message-yank-prefix is a variable defined in `message.el'.
Its value is

"> "

Documentation:
*Prefix inserted on the lines of yanked messages.
Fix `message-cite-prefix-regexp' if it is set to an abnormal value.
See also `message-yank-cited-prefix' and `message-yank-empty-prefix'.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 23.2 of Emacs.