JUN 01, 2016 09:28 AM PDT

Stick insects nab bacteria's genes

WRITTEN BY: Kerry Evans
We’re all familiar with vertical gene transfer (whether you know it or not). Vertical transfer describes the way you inherit genes from your parents, for example. What about horizontal (or lateral) gene transfer? This type of transfer occurs between two organisms that are not parent and offspring, and it occurs most often between unicellular organisms like bacteria.

However, researchers from the Max Planck Institute for Chemical Ecology report that stick insects acquired a bacterial gene (by horizontal transfer) from one of their gut microbes. Many investigators thought that gene transfer between bacteria and insects was quite rare, but new genomic techniques are challenging this idea.
 
Stick insects acquired bacterial genes.

Stick insects (also known as walking sticks) eat plants and need pectinases to digest the tough plant cell walls. Thing is, researchers didn’t think that stick insects could make their own pectinase - they thought gut bacteria made it for them.

That’s not the case. Matan Shelomi and colleagues at the Max Planck Institute found pectinase genes in the stick insect genome. Interestingly, the sequences of these genes are very similar to pectinase genes from gamma-proteobacteria - these bacteria are highly abundant in the stick insect’s gut.

The group used data from the 1K Insect Transcriptome Evolution Project (1KITE) to determine how long ago this horizontal transfer event occurred. They compared 1KITE data for Timema cristinae (a primitive species of stick insect that does not make pectinase) and the more modern Euphasmatodea (that do make pectinase). They concluded that the transfer event occurred between 60 and 100 million years ago.

This event is probably one reason why stick insects that make pectinase have spread so successfully around the world. When the insects are able to produce their own pectinase, they don’t have to rely on symbiotic microbes to do it for them.

According to study author Matan Shelomi, “something happened to make the tiny Timema become a planet-wide group of nearly 3,000 species that can be nearly half a meter long … the idea that genes from microbes living in our guts can suddenly become part of our genomes and change the course of our evolutionary history, that's an incredible finding”.
 

Sources: Nature Scientific Reports, Max Planck Institute for Chemical Ecology, 1KITE
 
About the Author
  • Kerry received a doctorate in microbiology from the University of Arkansas for Medical Sciences.
You May Also Like
NOV 13, 2019
Genetics & Genomics
NOV 13, 2019
Revealing the Epigenetic Patterns That Specific Enzymes Create
Genomic DNA is modified by chemical markers called epigenetic tags, which can change gene expression without altering the underlying genetic code....
NOV 13, 2019
Microbiology
NOV 13, 2019
Parasitic Worm Capable of Infecting People Now Found in Dogs
There are some small roundworms, also called nematodes, in the genus Strongyloides that can infect animals. Two species can infect people....
NOV 13, 2019
Genetics & Genomics
NOV 13, 2019
Gene Mutations Link Flu Infections and Heart Trouble
Sometimes people develop life-threatening heart complications when they're infected with the flu....
NOV 13, 2019
Microbiology
NOV 13, 2019
Large Study Shows That Birth Mode Impacts Infant Microbiome
The microbiome is impacted by mode of birth - babies born by Cesarean section have a different microbiome than babies born vaginally....
NOV 13, 2019
Microbiology
NOV 13, 2019
Early Ancestor of Animals Can Group Together and Coordinate Their Movements
After observing unusual microorganisms that had been collected in Curaçao, researchers saw a strange thing....
NOV 13, 2019
Microbiology
NOV 13, 2019
A New Strain of HIV is Identified
For the first time since 2000, researchers have identified a new subtype of HIV....
Loading Comments...