PARIS -- Neuroscientists in the United States believe they have identified a protein that blocks attempts to reconnect spinal-cord nerves that have been severed by injury.

Oligodendrocyte-myelin glycoprotein strongly inhibits the regrowth of nerve tissue in lab dishes, says a team led by He Zhigang of Harvard Medical School in Boston, Massachusetts.

The protein works via a receptor called nogo, located in myelin, the fatty sheath that surrounds nerve fibers.

Experts have long taken a close interest in nogo, believing it holds the molecular answer for solving many problems in spinal-cord damage.

The study was published Sunday in the online edition of **** Nature ****, the peer-reviewed British science journal.