Colo. – A team of scientists that includes researchers from the
University of Colorado Anschutz Medical Campus have sequenced the genome of the
Australian pitcher plant and discovered a key to the mystery of how those
plants became predatory.
pitcher plants evolved to include carnivorous pitcher leaves and
non-carnivorous flat leaves and that feature allowed the scientists to analyze
the genetic basis for carnivory by comparing the two types of leaves.
findings are reported in an article in the Feb. 6 issue of the journal Nature
Ecology and Evolution.
author Kenji Fukushima, PhD, began the pitcher plant genome project while a
graduate student under the guidance of co-author Mitsuyasu Hasebe, Professor at
the Graduate University for Advanced Studies (SOKENDAI) and National Institute
for Basic Biology (NIBB) in Japan. Fukushima is a postdoctoral research fellow
of the Japan Society for the Promotion of Science at the University of Colorado
School of Medicine, conducting research in the laboratory of David Pollock,
PhD, professor of biochemistry and molecular genetics.
team of scientists sequenced and analyzed the nuclear genome of the Australian
pitcher plant, which drowns its prey in an inescapable vat of digestive juices.
The team found changes in its genome that were linked to remarkable
characteristics of carnivorous plants such as prey attraction, trapping,
digestion and nutrient absorption.
or pitfall traps, are also a classic example of convergent evolution, a
phenomenon that occurs when distantly related organisms end up with similar
forms and function in response to similar environmental challenges. Their
convergent biology explains why the original
proponent of natural selection, Charles Darwin, shared Dr. Fukushima’s
fascination with carnivorous plants.
scientists analyzed pitcher plant digestive fluid, an enzyme cocktail secreted
from their specialized leaves, in three independently evolved pitcher plants
and a sticky carnivorous plant Drosera. The study concluded that in
addition to convergent digestive physiology, the separately arisen digestive
enzymes often incorporated similar genetic components, even though the lineages
had split more than 100 million years ago, long before their respective carnivorous
turns out that carnivorous plants are an amazing story of convergent evolution
in systems at multiple scales. The physiological convergence of leaf form and
function is associated with convergent evolution in enzyme repertoires, gene
expression patterns, and most strikingly, amino acid substitutions. Excess
convergence is strong evidence of natural selection, especially when found on
multiple scales,” said Pollock, who is a coauthor of the article along with
graduate Structural Biology and Biochemistry PhD student Stephen Pollard.
research team also included groups led by Victor Albert (University at Buffalo)
and Shuaicheng Li (BGI-Shenzhen and the University of Hong Kong in China).
full list of authors is available online. The title of the paper is “Genome
of the pitcher plant Cephalotus reveals genetic changes associated with