Featured Research

from universities, journals, and other organizations

Phenotype Is Influenced By Nature, Nurture And Noise

Date:
October 5, 2005
Source:
University of California - San Diego
Summary:
Geneticists have debated for decades the relative importance of nature versus nurture in determining how an animal looks and behaves, and now UCSD scientists report that noise could also be an important factor in determining phenotype.

While most biologists envision that gene regulation in a healthy cell runs like a Swiss watch, UCSD bioengineering professor Jeff Hasty says the process is full of unexpected variation.
Credit: Image courtesy of University of California - San Diego

In a paper in Proceedings of the National Academy ofSciences released online Sept. 30, the scientists led by bioengineeringprofessor Jeff Hasty and physicist Lev Tsimring reported thatunscripted biochemical variations, or noise, combined with time delaysin certain biochemical reactions may lead to oscillations in generegulation that couldn’t otherwise be predicted. Such noise isroutinely described by cell biologists who record large phenotypicdifferences between supposedly identical cells in a single flask ofgrowth medium.

“The mental picture many biologists have of ahealthy cell at the genetic level is of a smoothly running Swisswatch,” said Hasty. “But recent work in several labs around the countryare proving otherwise. The fine-grain fluctuations we see in thegenetic regulation within single cells may lead to new insights aboutvariability at the level of the whole organism.”

Changes in acell phenotype may be triggered by environmental factors, by programmedgenetic instructions, or more subtly by built-in delays in biochemicalpathways that generate oscillations, sometimes in 24-hour circadianperiods. Hasty, Tsimring, Dmitri Bratsun, and Dmitri Volfsonmodifiedthe Gillespie algorithm, a classical method of simulating stochasticchemical reactions, by factoring in time delays. Using the modifiedGillespie algorithm, coupled with a sophisticated theoretical analysis,the team discovered how the combination of intrinsic noise andbiochemical delays can lead to oscillations in gene expression whensuch variations are not expected in the absence of delays.

“Thisanalysis of gene regulation extends earlier explanations of theobserved variability of cells,” said Hasty. “The phenotype of anorganism is largely determined at the genetic level, so it is importantto zoom in on the noisy details of gene expression to explain thevariability that we couldn’t otherwise account for.”

Given thatthe coupling of 24-hour biological rhythms and the external environmentcan be crucial in the survival of an organism, the results may lead tonew insights into the importance of the synchronization of noisygenetic oscillations with the day-night cycle. “Our analysis provides aframework for addressing the role of noise and time delay in thegeneration of biological rhythms that are extremely important in manycontexts,” said Hasty.

###

Dmitri Bratsun, Dmitri Volfson, Lev S. Tsimring, and Jeff Hasty,"Delay-induced stochastic oscillations in gene regulation" (2005).Proceedings of the National Academy of Sciences.


Story Source:

The above story is based on materials provided by University of California - San Diego. Note: Materials may be edited for content and length.


Cite This Page:

University of California - San Diego. "Phenotype Is Influenced By Nature, Nurture And Noise." ScienceDaily. ScienceDaily, 5 October 2005. <www.sciencedaily.com/releases/2005/10/051005074900.htm>.
University of California - San Diego. (2005, October 5). Phenotype Is Influenced By Nature, Nurture And Noise. ScienceDaily. Retrieved August 30, 2014 from www.sciencedaily.com/releases/2005/10/051005074900.htm
University of California - San Diego. "Phenotype Is Influenced By Nature, Nurture And Noise." ScienceDaily. www.sciencedaily.com/releases/2005/10/051005074900.htm (accessed August 30, 2014).

Share This




More Plants & Animals News

Saturday, August 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

We've Got Mites Living In Our Faces And So Do You

We've Got Mites Living In Our Faces And So Do You

Newsy (Aug. 30, 2014) A new study suggests 100 percent of adult humans (those over 18 years of age) have Demodex mites living in their faces. Video provided by Newsy
Powered by NewsLook.com
Experimental Ebola Drug ZMapp Cures Lab Monkeys Of Disease

Experimental Ebola Drug ZMapp Cures Lab Monkeys Of Disease

Newsy (Aug. 29, 2014) In a new study, a promising experimental treatment for Ebola managed to cure a group of infected macaque monkeys. Video provided by Newsy
Powered by NewsLook.com
Killer Amoeba Found in Louisiana Water System

Killer Amoeba Found in Louisiana Water System

AP (Aug. 28, 2014) State health officials say testing has confirmed the presence of a killer amoeba in a water system serving three St. John the Baptist Parish towns. (Aug. 28) Video provided by AP
Powered by NewsLook.com
Raw: Australian Sheep Gets Long Overdue Haircut

Raw: Australian Sheep Gets Long Overdue Haircut

AP (Aug. 28, 2014) Hoping to break the record for world's wooliest, Shaun the sheep came up 10 pounds shy with his fleece weighing over 50 pounds after being shorn for the first time in years. (Aug. 28) 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