Understanding the insect enemy and its DNA
By Ruth SoRelle, M.P.H.
When researchers from Baylor College of Medicine, the U.S. Department of Agriculture and Kansas State University embarked on a project to sequence the genome of the red flour beetle, they had two goals in mind.
First, they knew they would be the first to sequence the genome of a beetle, thus advancing knowledge of how it and similar insects develop. Second, they hoped that better understanding of the insect's genetic makeup would help them develop tools to fight a pest that infests food products and wreaks considerable damage.
The red beetle is a voracious pest with an appetite that destroys millions of dollars worth of grain stored in flour mills. Also, the beetle serves as a model for studying the genetics of development – much in the way that scientists study fruit flies, or Drosophilae, to understand how genes can affect the ways in which organisms grow, said Stephen Richards, Ph.D., assistant professor in the Baylor College of Medicine Human Genome Sequencing Center. Richard Gibbs, Ph.D., of BCM directs the center.
More than 100 scientists from 14 countries took part in the Tribolium Genome Sequencing Consortium. The three-year project sped along, buoyed by the high through-put sequencing that is a hallmark of the BCM Genome Sequencing Center, which has led the sequencing efforts for the human genome as well as several model organisms.
A peek at pest biology
"The Tribolium genome sequence is the first for any beetle," said Dick Beeman, Ph.D., a research entomologist with the U.S. Department of Agriculture Agricultural Research Service in Manhattan, Kan. "Since beetles are the most diverse and successful animals on earth, this is an important milestone in evolutionary biology. Also, Tribolium is the first significant agricultural pest insect to have its genome revealed, and this creates new opportunities for understanding and exploiting pest biology."
"The genome sequence in combination with the ability to perform RNAi (a method that inhibits gene expression) at virtually any life stage makes Tribolium a premier insect model organism for studies that are not as readily accessible in Drosophila," said Susan J. Brown, Ph.D., professor of biology at Kansas State University. "It's really exciting to see the burst of activity in Tribolium studies that has accompanied the sequencing project."
Shared ancestry?
Richards said that some of the genes found in the beetle apparently share ancestry with similar genes in humans. For example, the gene for the receptor for vasopressin, which regulates how water is stored in the body, shares the same ancestry as the gene for the same hormone in humans.
"These beetles are good at living in dry environments," said Richards. "They survive partially on metabolic water, but 10 percent humidity in their environment is enough."
Beeman agreed, saying, "As just one example, more than 100 interesting genes associated with the exoskeleton have been identified, and many of these have been shown to have specific, vital functions. Tribolium has several attributes that make it unique among sequenced insects, including a preference for arid environments and a cosmopolitan palate."
"This independence of water makes Tribolium a prime candidate for a companion as a research organism during the long-term space flight such as the one planned for the red planet Mars," said Reinhard Schröder, Ph.D., of the University of Rostock, Germany, and a co-author of the study.
A consortium of researchers from many countries took part in this work, but Richards said Gregor Bucher of Georg August University in Göttingen, Germany; Roben Denell of Kansas State University in Manhattan, and Martin Klingler of Friedrich-Alexander-University in Erlangen, Germany, served as key leaders in completing the sequence and its analysis.
Funding for this research came from the National Human Genome Research Institute and the U.S. Department of Agriculture.
The full article can be found at http://www.nature.com/.
