XML Feed for RxPG News   Add RxPG News Headlines to My Yahoo!   Javascript Syndication for RxPG News

Research Health World General
 
  Home
 
 Latest Research
 Cancer
 Psychiatry
 Genetics
  X Chromosome
  Genetic Disorders
  Cloning
 Surgery
 Aging
 Ophthalmology
 Gynaecology
 Neurosciences
 Pharmacology
 Cardiology
 Obstetrics
 Infectious Diseases
 Respiratory Medicine
 Pathology
 Endocrinology
 Immunology
 Nephrology
 Gastroenterology
 Biotechnology
 Radiology
 Dermatology
 Microbiology
 Haematology
 Dental
 ENT
 Environment
 Embryology
 Orthopedics
 Metabolism
 Anaethesia
 Paediatrics
 Public Health
 Urology
 Musculoskeletal
 Clinical Trials
 Physiology
 Biochemistry
 Cytology
 Traumatology
 Rheumatology
 
 Medical News
 Health
 Opinion
 Healthcare
 Professionals
 Launch
 Awards & Prizes
 
 Careers
 Medical
 Nursing
 Dental
 
 Special Topics
 Euthanasia
 Ethics
 Evolution
 Odd Medical News
 Feature
 
 World News
 Tsunami
 Epidemics
 Climate
 Business
Search

Last Updated: Aug 19th, 2006 - 22:18:38

Genetics Channel
subscribe to Genetics newsletter

Latest Research : Genetics

   DISCUSS   |   EMAIL   |   PRINT
Synthetic biology experiment turns up a previously unrecognized gene-expression phenomenon
Feb 16, 2006, 19:47, Reviewed by: Dr. Priya Saxena

"This phenomenon could be relevant to bacterial 'persisters' - dormant cells that are highly resistant to antibiotics. Many bacterial pathogens can generate these persisters, which over many months can become the source of chronic infections. We don't understand the how persisters arise, but we think this unexpected gene-expression variability in bacterial cells is an interesting phenomenon that should be explored."

 
An experiment designed to show how a usually innocuous bacterium regulates the expression of an unnecessary gene for green color has turned up a previously unrecognized phenomenon that could partially explain a feature of bacterial pathogenicity.

In a paper published in the Feb. 16 issue of Nature, researchers at Boston University (BU) and the University of California, San Diego (UCSD) reported that computer modeling predicted the new phenomenon before they confirmed it in laboratory experiments. The group led by James J. Collins, a biomedical engineering professor at BU, and Jeff Hasty, a bioengineering professor at UCSD, reported that the rise and fall in the amount of green-fluorescence protein in computer modeling matched the pattern recorded in E. coli cells grown in various laboratory conditions.

The researchers were surprised that cell-to-cell variation in the expression of the synthetic gene increased sharply as growth slowed and then stopped. "We were initially skeptical of our own results because they were so counterintuitive," said Collins. "But our laboratory experiments confirmed this increase in gene-expression variability, or noise, when growth stops. We think there may be some very interesting biology to explore in this situation."

Variability in gene expression could offer distinct survival advantages to a bacterium. Like a cruise ship whose life boats have been stocked with different combinations of food, first-aid kits, rain jackets, and flotation devices, a microscopic version of Survivor could occur in which only those individual bacterial cells with opportune combinations of proteins are able to weather harsh growth conditions in a pond or even inside a human body.

"This phenomenon could be relevant to bacterial 'persisters' - dormant cells that are highly resistant to antibiotics," said Collins. "Many bacterial pathogens can generate these persisters, which over many months can become the source of chronic infections. We don't understand the how persisters arise, but we think this unexpected gene-expression variability in bacterial cells is an interesting phenomenon that should be explored."

The group of researchers came up with the novel finding by using a relatively new research approach that involves the synthesis of simple gene networks, in this case one that produces a green-fluorescence protein. They measured expression of green fluorescence in a laboratory strain of E. coli under different growth conditions where other genes and proteins could potentially complicate the situation. They incorporated that information into a mathematical model.

The authors say their findings demonstrate the value of a so-called "bottom-up" approach to synthetic biology: models of relatively simple cellular processes can be used to predict the behavior of larger, more complex ones.

"We're excited by this study because the model itself led to a counterintuitive prediction that was supported by experimentation," said UCSD's Hasty. "The logical next step is to examine noise in the expression of proteins that would be essential to a bacterium's survival," Hasty said. "We've only begun to get an inkling of how noise in gene expression may be involved in the life of a cell."
 

- Feb. 16 issue of Nature
 

www.ucsd.edu

 
Subscribe to Genetics Newsletter
E-mail Address:

 



Related Genetics News

New research into csd genes could help designing strategies for breeding honey bees
Williams Syndrome, the brain and music
Genetic mutation identified as cause of cranio-lenticulo-sutural dysplasia
Chance Fluctuations in mRNA Output in Mammalian Cells
Transposon Silencing Keeps Jumping Genes in Their Place
GATA2 - predicting susceptibility to coronary artery disease
Exploring genetics of congenital malformations
Genome insertions and deletions (INDELs) provide expanded view of human genetic differences
BRIT1 gene identified as protector of DNA
FDA Approves Idursulfase As First Treatment for Hunter Syndrome


For any corrections of factual information, to contact the editors or to send any medical news or health news press releases, use feedback form

Top of Page

 

© Copyright 2004 onwards by RxPG Medical Solutions Private Limited
Contact Us