DUBAI, Nov 22 (Reuters) - Saudi Investment Bank closed a 500 million riyals ($133.3 million) Tier 1 sukuk sale, the bank said on Tuesday. The subordinated Islamic bond, or sukuk, was sold privately, it added.

The debt transaction, which was completed on Monday, will boost the Riyadh-headquartered bank's capital base and its capital adequacy ratio, in addition to diversifying the Saudi bank's funding sources and its maturity profile, the bank said.

Alistithmar for Financial Securities and Brokerage Company and J.P. Morgan Saudi Arabia Company were the joint lead managers, it added.

($1 = 3.7503 riyals)

(Reporting by Davide Barbuscia; Editing by Tom Arnold) ((Davide.Barbuscia@thomsonreuters.com;))