Principal
Investigators:
Dr. Tanya Renner, San Diego State
University
Dr. Aman Gill, University of California,
Berkeley
Dr. Wendy Moore, University of
Arizona
Dr. Kipling Will, University of California,
Berkeley
Dr. Athula Attygalle, Stevens Institute of
Technology
Although powerful chemical weapons are rare in the animal world, some insects use them to protect themselves against their enemies. Bombardier beetles (Brachinus elongatulus) have taken this to an extreme. They explosively blast boiling hot, noxious chemicals from their abdomen at their predators. We propose to sequence the bombardier beetle genome to learn how this remarkable beetle makes these toxic chemicals, stores them within its body, and discharges them without self-injury.
Why is this the most interesting genome in the world?
Bombardiers are among the world's most impressive chemists. Unlike pheromones
used for communication, their genetic machinery provides for biochemical
warfare. They repel predators with rapid-fire, precisely-aimed explosive discharges of a toxic chemical mix
at over 100°C, earning them lead roles in media and culture. Yet the genomic basis of this
extraordinary ability remains a mystery. The first bombardier genome will allow
us to understand the genetic basis of bombardier chemical production, solving a
long-standing evolutionary puzzle. This understanding will elucidate the
currently unknown genetic basis of explosive chemical defense in the animal
kingdom.
What are the goals of this project?
Our goal is to
assemble the complete genome of the bombardier beetle, Brachinus
elongatulus, using PacBio's SMRT Sequencing technology. A Brachinus
genome (~500 Mb) will accelerate our ongoing National Science Foundation-funded
research, helping us to resolve the genetic basis of carabid beetle chemical
defense. We are currently using comparative transcriptomics to identify the
genes and biochemical pathways involved in the production of defensive
chemicals. The complete genome will elevate this research by i) revealing the
genomic architecture of biosynthesis genes and the regulatory factors
controlling their expression, ii) allowing us to pinpoint or exclude
biosynthetic roles played by microbes or horizontal gene transfer events, iii)
enabling comparative studies into the immense diversity of biosynthetic pathways
in other ground beetle species.
What is the global impact of your research?
The
Brachinus genome will be used by many researchers, as it will be the
first genome from a major branch of the tree of life, the beetle suborder
Adephaga, providing a unique point of comparison to other insects and to the few
existing beetle genomes, which are all from other suborders. We will use it to
provide a framework for understanding the genetic basis of defensive chemical
systems and a new foundation for research in chemical biosynthesis. Our
genome-based findings of the bombardier beetle will provide a solid
evidence-based explanation for their remarkable defensive strategy, shedding
light on a mystery that has given rise to extensive speculation but few solid
answers, thus making bombardier beetles a valuable and powerful evolutionary
case study for the classroom.
Project Team (in addition to PIs)
Additional Resource
Watch
the Bombardier beetle's "chemical cannon" in action