sacred-lotusScientists Sequence Genome of Sacred Lotus

A large team of genetic researchers has sequenced the genome of the sacred lotus (Nelumbo nucifera), which is believed to have a powerful genetic system that repairs genetic defects, and may hold secrets about aging.

Flower of Nelumbo nucifera (T. Voekler / CC BY-SA 3.0)

The sacred lotus is a symbol of spiritual purity and longevity. Its seeds can survive up to 1,300 years, its petals and leaves repel grime and water, and its flowers generate heat to attract pollinators.

“The lotus genome is an ancient one, and we now know its ABCs,” said Dr Jane Shen-Miller from the University of California, Los Angeles, senior author of a paper reporting the results in the journal Genome Biology.

“Molecular biologists can now more easily study how its genes are turned on and off during times of stress and why this plant’s seeds can live for 1,300 years. This is a step toward learning what anti-aging secrets the sacred lotus plant may offer.”

The sequence reveals that of all the plants sequenced so far – and there are dozens – sacred lotus bears the closest resemblance to the ancestor of all eudicots, a broad category of flowering plants that includes apple, cabbage, cactus, coffee, cotton, grape, melon, peanut, poplar, soybean, sunflower, tobacco and tomato.

First author Prof Ray Ming from the University of Illinois explained: “the plant lineage that includes the sacred lotus forms a separate branch of the eudicot family tree, and so lacks a signature triplication of the genome seen in most other members of this family.”

“Whole-genome duplications – the doubling, tripling of an organism’s entire genetic endowment – are an important events in plant evolution. Some of the duplicated genes retain their original structure and function, and so produce more of a given gene product – a protein, for example. Some gradually adapt new forms to take on new functions. If those changes are beneficial, the genes persist; if they’re harmful, they disappear from the genome.”

“Many agricultural crops benefit from genome duplications, including banana, papaya, sugarcane, strawberry, watermelon and wheat,” added co-author Robert VanBuren, also from the University of Illinois.

Although it lacks the 100 million-year-old triplication of its genome seen in most other eudicots, sacred lotus experienced a separate, whole-genome duplication about 65 million years ago, the researchers found. About 40 percent of the duplicated genes have been retained.

“A neat thing about the duplication is that we can look at the genes that were retained and see if they are in specific pathways,” VanBuren said.

The researchers found evidence that duplicated genes related to wax formation and survival in a mineral-starved watery habitat were retained, for example.

“By looking at changes in the duplicated genes, the researchers found that lotus has a slow mutation rate relative to other plants,” Prof Ming said. “These traits make lotus an ideal reference plant for the study of other eudicots.”