UPDATE 1- Nippon Life to raise $455 mln to strengthen capital

(Recasts with company confirmation)

TOKYO, Aug 18 (Reuters) - Japan's largest private life insurer Nippon Life Insurance said on Monday it plans to raise 50 billion yen ($455 million) from domestic institutional investors to strengthen its capital and to invest abroad.

Nippon Life, which has some 47 trillion yen in assets, has been forging alliances overseas as it seeks growth outside Japan's mature market and to expand its asset management expertise.

The insurer will issue bonds through early September as part of its plan to increase its total capital base to 4.7 trillion yen from 3.3 trillion yen, a Nippon Life spokesman said.

Daiwa Securities SMBC, an investment banking venture between Daiwa Securities Group (8601.T) and Sumitomo Mitsui Financial Group (8316.T), and Nomura Securities, part of Nomura Holdings (8604.T), will lead manage the issue.

Nippon Life said last month that it would take a 5 percent stake investment in U.S. fund and index group Russell Investments [ID:nT75558] and also recently lifted its stake in U.S.-based insurance company Principal Financial Group (PFG.N).

Its overseas portfolio also includes a stake in Bangkok Life Assurance. [ID:nBKK153097] (Reporting by Sachi Izumi; Editing by Edwina Gibbs)