Navigation Links
Pesky aphid thrives despite weak immune system
Date:2/22/2010

Pea aphids, expert survivors of the insect world, appear to lack major biological defenses, according to the first genetic analysis of their immune system.

"It's surprising," says Emory biologist Nicole Gerardo, who led the study, published this week in Genome Biology. "Aphids have some components of an immune system, but they are missing the genes that we thought were critical to insect immunity."

Pea aphids are major agricultural pests and also important biological models for studies of insect-plant interactions, symbiosis, virus vectoring and genetic plasticity. These resilient insects thrive despite a host of enemies, including parasitic wasps, lady bugs, fungal pathogens and frustrated farmers and gardeners the world over.

The immune-system analysis is among a group of findings being published this month as part of the International Aphid Genomics Consortium, which recently published the full sequence of the pea aphid genome, and sponsored dozens of in-depth analyses of different areas of the sequence. Gerardo served as a project leader for the consortium, in addition to heading the immune system study.

"This is the first look at the genome of a whole group of insects we know little about," says Gerardo, an evolutionary biologist who focuses on host-parasite interactions.

All insects previously sequenced, including flies and bees, belong to a group that undergoes metamorphosis. Pea aphids, however, belong to an insect group known as basel hemimetablous meaning they are born looking like tiny adults.

"We went into this expecting to find the same set of immune-system genes that we've seen in the genomes of flies, mosquitoes and bees," Gerardo says. "Given these missing genes, it seems that aphids have a weak immune system. Our next step is to figure out how they protect themselves."

One hypothesis is that aphids may compensate for their lack of immune defenses by focusing on reproduction. From birth, a female aphid contains embryos that also contain embryos.

"She is born carrying her granddaughters," Gerardo says. "In a lab, a female aphid can produce up to 20 copies of herself per day. About 10 days later, those babies will start producing their own offspring."

Over 50 million years, aphids have evolved complex relationships with beneficial bacteria that supply them with nutrients or protect them from predators and pathogens. It's possible that the weak immune response in aphids developed as a way to keep from killing off these beneficial microbes, Gerardo says. "A key question is whether these microbes could have changed the aphid genome, or changed how the aphid uses its genes."

Further study of how the aphid immune system interacts with microbes could yield better methods for controlling them in agriculture.

Aphids are not just pests, Gerardo says. They are also potential resources for questions related to human health.

"Humans need beneficial bacteria for proper digestion in the gut and to protect against cavities in the teeth," she says. "Some people feel sick when they take antibiotics because the drug kills off all the beneficial bacteria. If we can study the process of how to keep beneficial bacteria while clearing out harmful bacteria across several organisms, including aphids, we might be able to understand it better."


'/>"/>

Contact: Beverly Clark
beverly.clark@emory.edu
404-712-8780
Emory University
Source:Eurekalert  

Related biology news :

1. Pesky fruit flies learn from experienced females: Study
2. Transgenic maize is more susceptible to aphids
3. Eat up all of your Brussels sprouts -- unless youre an aphid
4. Aphids are sentinels of climate change
5. Discovering soybean plants resistant to aphids and a new aphid
6. Purple extremist thrives under inhospitable conditions
7. Ancient ecosystem thrives millions of years below Antarctic glacier
8. UGA licenses new Bermuda grass that thrives in sun and shade
9. CITES caviar export quotas remain steady for beluga sturgeon despite threat of extinction
10. Despite awareness of global warming Americans concerned more about local environment
11. Despite peacenik reputation, bonobos hunt and eat other primates too
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Pesky aphid thrives despite weak immune system
(Date:3/30/2017)... , March 30, 2017 The research ... system for three-dimensional (3D) fingerprint identification by adopting ground breaking 3D ... a new realm of speed and accuracy for use in identification, ... an affordable cost. ... ...
(Date:3/29/2017)... CHICAGO , March 29, 2017  higi, the ... ecosystem in North America , today ... Partners and the acquisition of EveryMove. The new investment ... extensive set of tools to transform population health activities ... and lifestyle data. higi collects and secures ...
(Date:3/27/2017)... 2017  Catholic Health Services (CHS) has been ... (HIMSS) Analytics for achieving Stage 6 on the ... In addition, CHS previously earned a place in ... electronic medical record (EMR). "HIMSS Analytics ... EMR usage in an outpatient setting.  This recognition ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... ... October 11, 2017 , ... Proscia Inc ., ... a Webinar titled, “Pathology is going digital. Is your lab ready?” with Dr. ... best practices and how Proscia improves lab economics and realizes an increase in ...
(Date:10/11/2017)... ... October 11, 2017 , ... Singh Biotechnology today announced ... to SBT-100, its novel anti-STAT3 (Signal Transducer and Activator of Transcription 3) B ... to cross the cell membrane and bind intracellular STAT3 and inhibit its function. ...
(Date:10/10/2017)... 2017 International research firm Parks Associates announced today ... the TMA 2017 Annual Meeting , October 11 in ... home security market and how smart safety and security products impact the ... Parks Associates: Smart Home Devices: ... "The residential security market has experienced ...
(Date:10/9/2017)... ... , ... The award-winning American Farmer television series will feature 3 Bar Biologics ... at 8:30aET on RFD-TV. , With global population estimates nearing ten billion people ... to feed a growing nation. At the same time, many of our valuable resources ...
Breaking Biology Technology: