MASTR MBS Classes Downgraded

Three tranches from two deals issued by MASTR Second Lien Trust have been downgraded by Moody's Investors Service, and one tranche has been placed under review for possible downgrade.The downgrades were as follows: series 2005-1, class M-8, from Ba2 to B1; and series 2006-1, class M-7, from Ba1 to B3, and class M-8, from Ba2 to Caa2. Class M-6 of the latter series was placed under review for possible downgrade. The rating actions were attributed to weaker-than-expected performance by the mortgage collateral and a resulting erosion of credit support. The underlying collateral for the deals consists of second-lien, fixed-rate residential mortgage loans. The collateral in the 2005-1 was primarily originated by Accredited Home Lender (42%) and the collateral in the 2006-1 was primarily originated by Fremont Investment & Loans (47%) and American Home (31%).