Researchers Sequence Genome of Sacred Lotus

Researchers have now sequenced the genome of the sacred lotus (Nelumbo nucifera).

The sacred lotus is a symbol of spirituality and non-attachment in China and India. The flower has waxy petals that repel water and its seeds are known to stay alive for more than 1,500 years.

The new study has given researchers new insight into the development of this revered flower. The study team found that the sacred lotus has great resemblance to the ancestor of many modern flowering plants that belong to eudicots - that includes apple, cabbage, coffee, melon, grape, tomato and sunflower.

Most plants that belong to the family show triplication of the genome. However, sacred lotus belongs to a subdivision that doesn't have this signature feature of the family. Genomic triplication has been attributed with early diversification of the family.

"Whole-genome duplications - the doubling, tripling (or more) of an organism's entire genetic endowment - are important events in plant evolution," said Ray Ming, professor at University of Illinois and lead author of the study.

He added that some of the duplicated genes continue to produce a plant product such as a protein. If the protein is found beneficial, the gene is retained, else it disappears from the plant genome.

"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," said Robert VanBuren, a graduate student in Ming's lab and one of the study authors.

The study showed that the plant had kept some genes, such as those needed to make the waxy substance, which helps it repel water.

Researchers found that the sacred lotus has been evolving slower than other eudicots. The plant experienced whole-genome duplication only about 65 million years ago, while the other plants diversified about 100 million years ago. Researchers say that the slow mutation rate of this plant makes it an ideal reference point to study other plants of the family.