NEW YORK ( TheStreet) -- Morgan Stanley ( MS) announced further changes to its management Thursday, elevating one of its most senior executives, while announcing the departure of a top fixed income trader.

Greg Fleming, a former Merrill Lynch president under Stan O'Neal who joined Morgan Stanley last year, becomes president of global wealth management while retaining responsibility for the company's asset management division, according to an internal memo from CEO James Gorman reviewed by TheStreet.

Wealth management includes Morgan Stanley Smith Barney, a business created after Morgan Stanley bought a controlling stake in Smith Barney from Citigroup ( C) in 2009. Asset management includes private equity, real estate and hedge fund investments, including a $1 billion mezzanine fund Morgan Stanley announced Wednesday.

Fleming replaces Charlie Johnston, who will retire at the end of 2011, staying on as Vice Chairman until the end of the year.

Also departing is Jack DiMaio who had been global head of interest rate credit and currency trading after being hired just 18 months ago. DiMaio was brought in to revive risk-taking at a division that failed to take advantage of market dislocations in the wake of the crisis as competitors like Goldman Sachs ( GS) had done. However, results under DiMaio were still unspectacular. Chief Risk Officer Ken deRegt will take over for DiMaio as global head of fixed income sales and trading. Keishi Hotsuki, a deputy to deRegt, will fill in on an interim basis.

The changes follow other senior level moves as chief operating officer Tom Nides left to join the U.S. state department.

Morgan Stanley was one of the weaker performers, at least in terms of share price, among large U.S. financial companies in 2010, CEO James Gorman's first year at the helm.

-- Written by Dan Freed in New York.
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