A marble-size lotus seed that lay dormant in a Manchurian dry lake bed for over 12 centuries is the oldest living seed ever germinated and could shed new light on the aging process, UCLA scientists said.

"A little seed that slept for more than 1,000 years sprouted in four days just like its modern sibling," said plant physiologist Jane Shen-Miller."It was there already when Marco Polo came to China in the 13th century," she said. "It has a powerful system to resist stress, drought, radiation. Now we have to study how it can maintain itself for this long period."

Shen-Miller was given seven of the ancient lotus seeds in 1982 by the Beijing Institute of Botany. Curious about their viability, she attempted to germinate four of them in 1983, getting three to sprout in the usual four-day germination period.

She then had the sprouts carbon dated, a process that killed the plants. But to Shen-Miller's astonishment, the process revealed that they were 1,288 and 684 years old.

Ten years later, she was giving a lecture on the ancient seeds that was attended by Steven Clarke, a University of California, Los Angeles, biochemist who specializes in the chemistry of aging.

"We're very interested in looking at these seeds, because we think they hold some secrets for understanding aging, and how that tissue could be sitting out there in nature for 1,000 years and still be able to create a new plant on four days' notice," Clarke said.

The 1,288-year-old seed is now one of four ancient seeds germinated by Shen-Miller, who grew a 332-year-old seed to a full-size plant that died because she didn't know how to care for it.

Advances in technology now allow the plants to be carbon dated without being killed.

Shen-Miller said she is attempting to get more of the seeds from China to continue the research into the enzymes that help keep the seeds alive.

Chemists working with Clarke have isolated a protein-repair enzyme, methyltransferase, which they said was surprisingly as viable as the enzyme in a new plant.

Further research into the enzyme could lead to heartier seeds in wheat and corn plants and possibly hold secrets to the aging process in humans, the scientists said.