* U.S. stock index futures pointed to a slightly lower open on Wall Street on Monday, as bleak data out of Japan rekindled fears over a prolonged global downturn, but a tentative rebound in commodity prices could boost mining and oil shares. * Volumes were expected to remain thin in Christmas week. * At 0953 GMT S&P 500 March futures SPc1 were down 0.3 percent, Dow Jones futures DJc2 were down 0.2 percent and Nasdaq 100 futures NDc2 were down 0.1 percent. * The macroeconomic newsflow remained grim, with Japan on Monday warning it is sliding deeper into recession after data showed the biggest ever drop in exports in November while a Reuters Tankan monthly survey showed business sentiment at the lowest in its 10-year history and Bank of Japan Governor Masaaki Shirakawa said the worst was yet to come. * Despite the rescue package unveiled last week, the auto sector could feel the pinch of Toyota Motor Co's (7203.T) second profit warning in two months, as the world's top car maker predicted a group operating loss of 150 billion yen ($1.7 billion) for the year to end-March -- hit by the global slump in car sales and a crippling rise in the yen. * No major macro data was due on Monday, while on the earnings front, companies expected to report earnings include Walgreen (WAG.N). * Oil rose to near $43 a barrel on Monday, helped by tough talk from top OPEC producers of compliance with their record output cut and a weaker U.S. dollar, while U.S. data showed speculators betting on a bounce. * Shanghai copper futures bounced by their 4 percent daily limit on Monday, recovering from a five-year low in the previous session, supported by the rescue plan for U.S. carmakers and a weaker dollar. * German reinsurer Munich Re (MUVGn.DE) will pay $742 million in cash to buy American International Group Inc's (AIG.N) HSB Group as a way to expand its U.S. business, the companies said on Monday. (Reporting by Blaise Robinson; Editing by Victoria Bryan)

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