PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Genes define the interaction of social amoeba and bacteria

2013-05-09
(Press-News.org) HOUSTON -- (May 9, 2013) – Amoeba eat bacteria and other human pathogens, engulfing and destroying them – or being destroyed by them, but how these single-cell organisms distinguish and respond successfully to different bacterial classes has been largely unexplained.

In a report in the journal Current Biology, researchers from Baylor College of Medicine use the model of the social amoeba – Dictyostelium discoideum – to identify the genetic controls on how the amoeba differentiate the different bacteria and respond to achieve their goal of destruction.

"No one has looked at the basic question of what happens when you put the two classes of species together," said Dr. Adam Kuspa, professor in the department of biochemistry & molecular biology and senior vice president for research at BCM. "What does the amoeba do?"

The scientists, who included first author graduate student Waleed Nasser, did a genetic screen called a transcriptional profile, that identified sets of genes are active or expressed when interacting with two major classes of bacteria -- gram negative and gram positive.

"The two kinds of bacteria are different in structure and biochemistry," said Kuspa, who is the corresponding author of the report. "We found that the Dictyostelium did differentiate between the different bacteria. In fact, it was shocking that nearly 800 different genes were activated when exposed to a kind of gram negative bacteria known as enterobacteria (Klebsiella)."

The researchers found 50 amoebal genes that were activated during growth on gram negative species of bacteria and 68 that were activated on gram positive species. The genes identified as active on gram positive bacteria were those most commonly defined as involved in metabolism. Those active on gram negative bacteria were most likely involved in degrading the cell wall, in particular one gene called alyL, which encodes an amoeba protein which likely acts as a lysozyme, an enzyme that breaks down bacterial cell walls. They also identified glucose-6-phosphate or a metabolite of it as signaling the presence of gram positive bacteria.

From that, said Kuspa, the question arises of whether this "barometer" of the presence of gram positive bacteria in the social amoeba might be conserved across evolution in humans.

"Might it be conserved in us?" he asked.

When the genome of the social amoeba was sequenced, Kuspa, colleague Dr. Gad Shaulsky, professor of molecular and human genetics at BCM, and others found that all amoeba are related. That means that what affects one kind of amoeba probably affects another.

"The second thing was that we found amoebae are more closely related to us than we thought," said Kuspa. Many of the proteins found in amoeba are conserved in mammals.

"We hope that what we learn from amoebae might be relevant to human immune systems," he said.

Others who took part in this work include Shaulsky, Balaji Santhanam, Edward Roshan Miranda, Anup Parikh Chris Dinh, Rui Chen and Blaz Zupan, all of BCM; and Kavina Juneja of Rice University and Gregor Rot of the University of Ljubljana in Slovenia. Zupan is also of the University of Ljubljana.

###

Funding for this work came from the Dictyostelium Functional Genomics Program Project Grant from the National Institutes of Health (PO1 HD39691).

For more information on research at Baylor College of Medicine, please go to http://www.bcm.edu/fromthelab.

END



ELSE PRESS RELEASES FROM THIS DATE:

Turning old hearts

2013-05-09
Cambridge, MA, May 9, 2013 - Two Harvard Stem Cell Institute researchers – one a stem cell biologist and one a practicing cardiologist at Brigham and Women's Hospital – have identified a protein in the blood of mice and humans that may prove to be the first effective treatment for the form of age-related heart failure that affects millions of Americans. When the protein, called GDF-11, was injected into old mice, which develop thickened heart walls in a manner similar to aging humans, the hearts were reduced in size and thickness, resembling the healthy hearts of younger ...

Advance in tuberous sclerosis brain science

2013-05-09
PROVIDENCE, R.I. [Brown University] — Doctors often diagnose tuberous sclerosis complex (TSC) based on the abnormal growths the genetic disease causes in organs around the body. Those overt anatomical structures, however, belie the microscopic and mysterious neurological differences behind the disease's troublesome behavioral symptoms: autism, intellectual disabilities, and seizures. In a new study in mice, Brown University researchers highlight a role for a brain region called the thalamus and show that the timing of gene mutation during thalamus development makes a huge ...

Dad's genome more ready at fertilization than mom's is -- but hers catches up

2013-05-09
SALT LAKE CITY—Researchers from Huntsman Cancer Institute (HCI) at the University of Utah have discovered that while the genes provided by the father arrive at fertilization pre-programmed to the state needed by the embryo, the genes provided by the mother are in a different state and must be reprogrammed to match. The findings have important implications for both developmental biology and cancer biology. In the earliest stages, embryo cells have the potential to develop into any type of cell, a state called totipotency. Later, this potency becomes restricted through ...

Gene identified, responsible for a spectrum of disorders affecting the bones and connective tissue

2013-05-09
Researchers from the RIKEN Center for Integrative Medical Sciences have identified a gene that when mutated is responsible for a spectrum of disorders affecting the bones and connective tissue. This finding opens new avenues for research into a diagnosis and treatment for these until now incurable diseases. The study is published today in the American Journal of Human Genetics. Spondyloepimetaphyseal dysplasia with joint laxity, type I or SEMD-JL1 is a disorder of the skeleton resulting in short stature and spinal problems starting from birth, and worsening with age. ...

Exit discovered in cellular garbage truck

2013-05-09
At the University of Geneva (UNIGE), the team led by Professor Jean Gruenberg has long been interested in the movement of lysosomes, the sub-compartments of cells to where endocytic vesicles deliver their waste content and the molecules destined to be destroyed. Within this context, researcher Christin Bissig, along with her international colleagues, carried out a detailed study of the route taken by Alix which is lodged inside the endosomal membrane. This tailing has highlighted how protein contributes to avoiding cellular digestion, like a door opening into the endosomal ...

Operating without interrupting warfarin reduces risk of bleeding after cardiac device surgery

2013-05-09
DENVER, May 9, 2013 – A new Canadian study shows that operating without interrupting warfarin treatment at the time of cardiac device surgery is safe and markedly reduces the incidence of clinically significant hematomas compared to the current standard of care. The new findings were released today at Heart Rhythm 2013, the Heart Rhythm Society's 34th Annual Scientific Sessions, and will be published online today in The New England Journal of Medicine (NEJM). At least a quarter of patients that require pacemaker or implantable defibrillator surgery are taking warfarin ...

Scripps Research Institute scientists find key to gene-silencing activity

2013-05-09
LA JOLLA, CA – May 9, 2013 – A team led by scientists at The Scripps Research Institute (TSRI) has found how to boost or inhibit a gene-silencing mechanism that normally serves as a major controller of cells' activities. The discovery could lead to a powerful new class of drugs against viral infections, cancers and other diseases. "Learning to control natural gene silencing processes will allow an entirely new approach to treating human disease," said Ian J. MacRae, assistant professor in TSRI's Department of Integrative Structural and Computational Biology and principal ...

Studies generate comprehensive list of genes required by innate system to defend sex cells

2013-05-09
Cold Spring Harbor, NY – Two teams of investigators led by Professor Gregory Hannon of Cold Spring Harbor Laboratory (CSHL) today publish studies revealing many previously unknown components of an innate system that defends sex cells – the carriers of inheritance across generations – from the ravages of transposable genetic elements. When activated, these troublesome segments of DNA, also called jumping genes or transposons, can copy and insert themselves at random spots across the chromosomes. In sperm and egg cells the proliferation of transposons can be particularly ...

Scientists show how nerve wiring self-destructs

2013-05-09
Many medical issues affect nerves, from injuries in car accidents and side effects of chemotherapy to glaucoma and multiple sclerosis. The common theme in these scenarios is destruction of nerve axons, the long wires that transmit signals to other parts of the body, allowing movement, sight and sense of touch, among other vital functions. Now, researchers at Washington University School of Medicine in St. Louis have found a way the body can remove injured axons, identifying a potential target for new drugs that could prevent the inappropriate loss of axons and maintain ...

No holes in Swiss online networking theory

2013-05-09
Often, it's not what you know, but who you know when it comes to business and research success and that still applies even in the age of online social networking, according to results to be published in the International Journal of Organisational Design and Engineering. Peter Gloor, Pierre Dorsaz, Hauke Fuehres and Manfred Vogel of the MIT Center for Collective Intelligence, in Cambridge, Massachusetts have compared the success of startup entrepreneurs and innovators with their activity on the social networking sites LinkedIn and Facebook as well as email networks including ...

LAST 30 PRESS RELEASES:

How NIL boosts college football’s competitive balance

Moffitt researchers develop machine learning model to predict urgent care visits for lung cancer patients

Construction secrets of honeybees: Study reveals how bees build hives in tricky spots

Wheat disease losses total $2.9 billion across the United States and Canada between 2018 and 2021

New funding fuels development of first potentially regenerative treatment for multiple sclerosis

NJIT student–faculty team wins best presentation award for ant swarm simulation

Ants defend plants from herbivores but can hinder pollination

When the wireless data runs dry

Inquiry into the history of science shows an early “inherence” bias

Picky eaters endure: Ecologists use DNA to explore diet breadth of wild herbivores

Study suggests most Americans would be healthier without daylight saving time

Increasing the level of the protein PI31 demonstrates neuroprotective effects in mice

Multi-energy X-ray curved surface imaging-with multi-layer in-situ grown scintillators

Metasurface enables compact and high-sensitivity atomic magnetometer

PFAS presence confirmed in the blood of children in Gipuzkoa

Why do people believe lies?

SwRI installs private 5G network for research, development, testing and evaluation

A new perspective in bone metabolism: Targeting the lysosome–iron–mitochondria axis for osteoclast regulation

Few military spouses use formal support services during, after deployment

Breakthrough in the hunt for light dark matter: QROCODILE project reveals world-leading constraints

2D x-ray imaging technique reveals hidden processes in CO2 electrolyzers

Rational high entropy doping strategy via modular in-situ/post solvothermal doping integration for microwave absorption

Circular Economy has been officially included in the ESCI

Recent advances in exciton-polariton in perovskite

Efficacy and safety of GLP-1 RAs in children and adolescents with obesity or type 2 diabetes

Over-the-counter sales of overdose reversal drug naloxone decline after initial surge

Global trends and disparities in social isolation

Country of birth, race, ethnicity, and prenatal depression

Kissick Family Foundation, Milken Institute announce $2 million in funding for frontotemporal dementia research and new call for proposals

Mayo Clinic study reveals hidden causes of heart attacks in younger adults, especially women

[Press-News.org] Genes define the interaction of social amoeba and bacteria