UPDATE 1-Novartis invests $1 bln in China R&D plant

* Emphasises importance of emerging markets

* Invests further $250 mln in second plant

ZURICH, Nov 3 (Reuters) - Swiss drugmaker Novartis AG (NOVN.VX) is investing $1 billion to build the largest pharmaceutical research plant in China, emphasising the importance of developing markets for future growth.

Novartis and other drugmakers are keen to tap into markets such as China as they face slowing growth and loss of exclusivity on key products, including the Swiss group's top-selling blood pressure medicine Diovan. Novartis said it was also investing $250 million in a second research and development and manufacturing facility in Changshu. (Reporting by Sam Cage; Editing by Mike Nesbit)