RFC 2369 describes various headers that are designed to facilitate manipulation with mailing lists. Currently, the modest e-mail client doesn't recognize any of them or treat them specially.
In desktop mail clients, at the very least, usually the List-Post command is used to provide a "reply to list" option in addition to the regular "reply" and "reply-all" options. Often List-Unsubscribe or List-Help are also presented to the user.
Screen real-estate is precious for modest, which presents a question of how this information should be surfaced to the user (if at all).