State Rep. Marie St. Fleur, who earlier this year announced that she will not seek re-election this fall, will be joining the administration of Boston Mayor Thomas Menino, according to a press release from Menino's office today. Her title in Menino's office will be Chief of Advocacy and Strategic Investment, which oversees Menino's lobbying efforts through his Intergovernmental Relations Offices. St. Fleur will begin her new duties in June, according to Menino's office.