Jupiter sees Q1 asset boost from investment gains, inflows

* Assets under management up 7.4 pct to 43.5 bln stg

* Net (LSE: 0LN0.L - news) mutual fund inflows 1.4 bln stg

* Shares (Berlin: DI6.BE - news) up 3.4 pct, leading FTSE mid-cap gainers (Adds analyst quote, share reaction, background)

By Simon Jessop

LONDON, April 26 (Reuters) - Jupiter Fund Management said market gains and net inflows of new money from clients across its range of funds helped the British firm raise its total assets under management by 7.4 percent in the first quarter.

The strong start to the year mirrors quarterly asset gains for rivals Man Group (LSE: EMG.L - news) and Ashmore, although the market backdrop remains tough amid rising competition from index-tracking funds and pressure on fees from investors.

Net mutual fund inflows amounted to 1.4 billion pounds ($1.8 billion) in the three months to March 31, with overall net inflows of 1.3 billion, it said in a statement.

Combined with a 1.7 billion-pound boost from market and currency movements, that helped raise total assets under management to 43.5 billion pounds from 40.5 billion at the end of December, with the news sending Jupiter's shares up 3.7 percent to 482 pence in early trading on Wednesday.

"The continued strategy to diversify our business by product, client type and geography and delivery of strong investment performance after fees across a broad range of strategies has resulted in good inflows both internationally and within the UK," Chief Executive Maarten Slendebroek said.

Jupiter said it had seen significant flows into its Fixed Income, Absolute Return, Multi Asset and Global Emerging Market strategies. Demand from clients in Asia and continental Europe had been particularly strong, it said.

KBW analyst Jonathan Richards said Jupiter's strong net inflows were 3 percent better than expected, while total assets under management was 2 percent better.

Given a 10 percent run-up in Jupiter's share price over the previous month, Richards said the valuation was fair and so reiterated a 'market perform' rating. ($1 = 0.7800 pounds) (Reporting by Simon Jessop; Editing by Greg Mahlich)