The age old saying “cool as a cucumber” has an entirely new meaning after recent scientific discoveries. Recently, this vegetable has been at the center attention of plant biologists around the world. The discovery of the cucumber’s genome has promising impacts for our communities and plant science research.
UC Davis, in partnership with Chinese and U.S. research institutions, sequenced the cucumber genome that was published Nov. 1 by the journal Nature Genetics.
“The impact of discovering any genome allows scientists to examine overall gene evolution and accelerate progress on the analysis of individual gene components that reveal more about the organism,” said William Lucas, chair of the UC Davis department of plant biology.
Lucas is primarily interested in plant vascular transport systems, the phloem and xylem; more specifically, how these structures function in the whole communication of the plant. He is also the co-author of the research, and assisted in the development and management of the cucumber genome research project.
But the question remains, why cucumbers?
“Based on my experience on the farm in Australia with my mother many, many years ago, I turned to cucurbits, that’s why cucumbers,” Lucas said.
Cucumbers belong to the cucurbit family, which includes watermelons, pumpkins, melons and squash.
“The cucumber, in their evolution, became the hemophiliacs of the plant kingdom. When you cut the vascular tissue of a cucurbit it bleeds the blood of the phloem. That means you can get the analytical qualities of the phloem cell,” Lucas said.
The vascular system – phloem – of the cucumber is easily accessible, which makes this plant ideal for research.
Complete genome of the cucumber has paved the way for plant scientists to identify certain proteins and signal molecules in the phloem sap more rapidly. Moreover, Lucas’ research group has already linked many of these signaling proteins to be involved in the plant’s growth, coordination of activity, nutrient signaling and defense.
Many vital proteins and molecules are transported through the plant phloem, said Brian Ham, a post-doctoral fellow who is part of Lucas’ research team.
“If we can understand the phloem, we can control the phloem, which will allows us to control the plant growth rate, flowering time and defenses against viruses,” Ham said. “We strongly believe that if we understand the phloem, we can control the development and pathology of the plant.”
Lijun Liu, a post-doctoral fellow who works in Lucas’ research lab said that the cucumber and pumpkin are genetically similar.
“The genome data from the cucumber is useful in understanding more about the pumpkin and other model plants,” Liu said.
Professor Sanwen Huang of the Chinese Academy of Agricultural Science and the Beijing Genome Institute-Shenzhen – collaborators on the cucumber genome project – created new sequencing methods that assemble short pieces of DNA. This allows for faster gene sequencing using lower costs.
“This genome database will accelerate so many aspects of basic biology and agricultural production, but it’s not going to be a walk in the park. However, without these tools, it’s very difficult,” Lucas said.
SRI RAMESH can be reached at firstname.lastname@example.org.