MARM0507-FINAL -- 2A1

UBS AG

Balance Coupon

Settle

$231,731,000.00

5.400849

08/30/2005

Delay

Dated First Payment

08/01/2005

09/25/2005

WAC(2)

NET(2)

5.758215

5.400849

WAM(2)

WALA(2)

358

Price	5		10	15	20	25	30	35	40	45	50
		Yield	Yield	Yield	Yield	Yield	Yield	Yield	Yield	Yield	Yield
100-31		5.099	5.050	4.994	4.932	4.862	4.782	4.691	4.588	4.474	4.339
101-00		5.091	5.040	4.983	4.920	4.848	4.766	4.673	4.568	4.451	4.313
101-01		5.082	5.031	4.972	4.907	4.834	4.750	4.655	4.548	4.428	4.287
101-02		5.074	5.021	4.961	4.895	4.820	4.734	4.637	4.527	4.405	4.261
101-03		5.065	5.011	4.950	4.883	4.806	4.718	4.619	4.507	4.382	4.235
101-04		5.057	5.002	4.939	4.870	4.792	4.702	4.601	4.487	4.359	4.209
101-05		5.048	4.992	4.928	4.858	4.778	4.687	4.584	4.467	4.336	4.183
101-06		5.040	4.983	4.918	4.846	4.764	4.671	4.566	4.447	4.314	4.157
101-07		5.031	4.973	4.907	4.833	4.750	4.655	4.548	4.426	4.291	4.131
101-08		5.023	4.963	4.896	4.821	4.736	4.639	4.530	4.406	4.268	4.105
101-09		5.014	4.954	4.885	4.809	4.722	4.624	4.512	4.386	4.245	4.079
Spread @ Center Price		60	56	51	46	39	32	23	15	4	-9
WAL		4.17	3.65	3.20	2.80	2.46	2.16	1.89	1.65	1.45	1.27
Principal Window		Sep05 - Jun10	Sep05 - Jun10	Sep05 - Jun10	Sep05 - Jun10	Sep05 - Jun10	Sep05 - Jun10	Sep05 - Jun10	Sep05 - Jun10	Sep05 - Jun10	Sep05 - Jun10
LIBOR_6MO		4.06	4.06	4.06	4.06	4.06	4.06	4.06	4.06	4.06	4.06
LIBOR_1YR		4.27	4.27	4.27	4.27	4.27	4.27	4.27	4.27	4.27	4.27
Prepay		5 CPB	10 CPB	15 CPB	20 CPB	25 CPB	30 CPB	35 CPB	40 CPB	45 CPB	50 CPB
Optional Redemption		Call (N)	Call (N)	Call (N)	Call (N)	Call (N)	Call (N)	Call (N)	Call (N)	Call (N)	Call (N)

Yield Curve

Mat

1MO

3MO

6MO

1YR

2YR

3YR

5YR

10YR

30YR

Yld

3.66938

3.86

4.06

4.27

4.3795

4.419

4.475

4.601

4.818

UBS Securities LLC. This material has been prepared by UBS AG or an affiliate thereof (" UBS"). It has no regard to the specific investment objectives, financial situation or particular needs of any specific recipient.

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MORTGAGE ASSET SECURITIZATION TRANSACTIONS INC 8-K