Single-cell parasites co-opt 'ready-made' genes from host: study

July 18, 2012

Two species of single-cell parasites have co-opted "ready-made" genes from their hosts that in turn help them exploit their hosts, according to a new study by University of British Columbia and University of Ottawa researchers.

Part of a group of parasitic called microsporidia, Encephalitozoon hellem and Encephalitozoon romaleae are related to fungi and are commonly found in the of . In humans, they are associated with people with immune deficiencies.

The research team identified six genes in these parasites that were not found in any other microsporidian. Rather than the slow process of inheriting individual genes, E. hellem and E. romaleae have acquired a suite of genes that produce folate, a form of folic acid that helps cell division and growth.

"With their tiny, reduced genomes, microsporidia are models for ," says lead author Patrick Keeling, a professor in UBC's Dept. of Botany.

"These parasites have undergone massive reductions and are literally infection machines – they only kept genes that are essential for survival."

"But here we found two species have actually acquired new genes that work together to make an essential nutrient that the parasites would otherwise have to steal from their host – opening up new tissues or even new hosts as targets for infection," says Keeling, director of the Centre for Microbial Diversity and Evolution and a member of Beaty Biodiversity Research Centre at UBC.

The process of horizontal gene transfer – the ability to acquire ready-made genes with specific functions from foreign genomes – is an important but often overlooked mechanism of evolution, according to Keeling. "It helps explain the relatively rapid evolution of these tiny organisms and their ability to infect and live off of a wide variety of hosts."

Explore further: Mutant parasites, unable to infect hosts, highlight virulence genes

Related Stories

Tiny fungi may have sex while infecting humans

October 30, 2008

A fungus called microsporidia that causes chronic diarrhea in AIDS patients, organ transplant recipients and travelers has been identified as a member of the family of fungi that have been discovered to reproduce sexually. ...

Recommended for you

Stressed out plants send animal-like signals

July 29, 2015

University of Adelaide research has shown for the first time that, despite not having a nervous system, plants use signals normally associated with animals when they encounter stress.

Sex among eukaryotes is far more common than once believed

July 28, 2015

(Phys.org)—For a long time, biologists have considered sex to be an inherent trait of multicellular life, while microbial eukaryotes were considered to be either optionally sexual or purely clonal. From this perspective, ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.