Featured Research

from universities, journals, and other organizations

Evolutionary Harmony For Stinkbugs And Their Gut Bacteria: A Perfect Match

Date:
October 11, 2006
Source:
Public Library of Science
Summary:
Evidence of host-symbiont cospeciation in an insect gut symbiont suggests that long-term vertical transmission and population structure are central forces driving the genomic changes characteristic of insect nutritional symbionts, according to a study published in PLoS Biology.

A mating pair of the Japanese common plataspid stinkbug Megacopta punctatissima.
Credit: Photo: Fukatsu et al. / courtesy of PLoS Biology

With some 1 million species and counting, insects may be the most abundant class of animals living today. Their protective exoskeleton, prolific reproductive rate, and wings help their cause, as do the symbiotic bacteria that inhabit their cells, gut, or body cavity. Endocellular symbionts live inside specialized insect cells and provide essential nutrients for their hosts, and this exclusive relationship often means that the evolutionary history of one matches the other. Gut or body cavity symbionts, however, are vulnerable to displacement or attack by other microbes and are thought to have less-exclusive relationships with their hosts.

But a new study published in the open access journal PLoS Biology suggests that not all gut symbionts opt for the more promiscuous lifestyle. Takahiro Hosokawa, Takema Fukatsu, and colleagues provide the first evidence of cospeciation between a group of gut symbionts and their insect hosts, plataspid stinkbugs. Not only do their evolutionary histories mirror each other, but the gut symbionts share many of the unique genetic traits typical of endocellular symbionts.

Plataspid stinkbug symbionts live in the bugs' posterior midgut and are vertically transmitted by the mother in symbiont "capsules." When the female lays eggs, small, brown symbiont-filled capsules always appear under the egg mass. Nymph hatchlings ingest symbionts from the capsule.

Hosokawa et al. collected 12 populations of stinkbugs, representing three genera and seven species, from several locations in Japan. The researchers analyzed the DNA of the resident bacteria from four of the species and found that each bacterial species was associated with a different stinkbug species and fell into their own class of Proteobacteria, but were closely related to the well-characterized obligate endosymbiont (Buchnera aphidocola) of aphids.

The authors also showed that adult stinkcbugs lacking symbionts showed developmental delays, grew smaller, failed to copulate or reproduce, and died prematurely. Just as aphids depend on their endosymbionts, plataspid stinkbugs depend on their gut symbionts to survive. And, like Buchnera, the gut endosymbionts also appear to have co-evolved with their host.

The phylogenetic tree of the stinkbugs, the researchers found, "perfectly agreed" with the phylogenetic relationships of the gut symbionts. Moreover, the symbiotic lifestyle that has shaped the genome evolution of endocellular symbionts like Buchnera also applies to these gut symbionts. The authors found the same intriguing pattern of a small genome, a high percentage of A and T nucleotides in their DNA, and accelerated molecular evolution, thought to possibly result from population genetic forces--for example, small population size and bottlenecks.

Hosokawa et al. have named these gut symbionts "Candidatus Ishikawaella capsulata," in honor of Hajime Ishikawa, a pioneer in the molecular study of symbiosis, who recently passed away. With some 530 species and 56 genera in the Plataspidae family, researchers have their work cut out for them as they survey the lineages for a stinkbug without a capsule. But with this unique plataspid stinkbug system, they will be well equipped to study insect symbiosis and its influence on genome evolution.

Citation: Hosokawa T, Kikuchi Y, Nikoh N, Shimada M, Fukatsu T (2006) Strict host-symbiont cospeciation and reductive genome evolution in insect gut bacteria. PLoS Biol 4(10): e337. DOI: 10.1371/journal.pbio.0040337.


Story Source:

The above story is based on materials provided by Public Library of Science. Note: Materials may be edited for content and length.


Cite This Page:

Public Library of Science. "Evolutionary Harmony For Stinkbugs And Their Gut Bacteria: A Perfect Match." ScienceDaily. ScienceDaily, 11 October 2006. <www.sciencedaily.com/releases/2006/10/061010022925.htm>.
Public Library of Science. (2006, October 11). Evolutionary Harmony For Stinkbugs And Their Gut Bacteria: A Perfect Match. ScienceDaily. Retrieved September 22, 2014 from www.sciencedaily.com/releases/2006/10/061010022925.htm
Public Library of Science. "Evolutionary Harmony For Stinkbugs And Their Gut Bacteria: A Perfect Match." ScienceDaily. www.sciencedaily.com/releases/2006/10/061010022925.htm (accessed September 22, 2014).

Share This



More Plants & Animals News

Monday, September 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: San Diego Zoo Welcomes Cheetah Cubs

Raw: San Diego Zoo Welcomes Cheetah Cubs

AP (Sep. 20, 2014) The San Diego Zoo has welcomed two Cheetah cubs to its Safari Park. The nearly three-week-old female cubs are being hand fed and are receiving around the clock care. (Sept. 20) Video provided by AP
Powered by NewsLook.com
Chocolate Museum Opens in Brussels

Chocolate Museum Opens in Brussels

AFP (Sep. 19, 2014) Considered a "national heritage" in Belgium, chocolate now has a new museum in Brussels. In a former chocolate factory, visitors to the permanent exhibition spaces, workshops and tastings can discover derivatives of the cocoa bean. Duration: 01:00 Video provided by AFP
Powered by NewsLook.com
Could Grief Affect The Immune Systems Of Senior Citizens?

Could Grief Affect The Immune Systems Of Senior Citizens?

Newsy (Sep. 19, 2014) The study found elderly people are much more likely to become susceptible to infection than younger adults going though a similar situation. Video provided by Newsy
Powered by NewsLook.com
Jury Delivers Verdict in Salmonella Trial

Jury Delivers Verdict in Salmonella Trial

AP (Sep. 19, 2014) A federal jury has convicted three people in connection with an outbreak of salmonella poisoning five years ago that sickened hundreds of people and was linked to a number of deaths. (Sept. 19) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins