Navigation Links
Large DNA stretches, not single genes, shut off as cells mature
Date:1/18/2009

Experiments at Johns Hopkins have found that the gradual maturing of embryonic cells into cells as varied as brain, liver and immune system cells is apparently due to the shut off of several genes at once rather than in individual smatterings as previous studies have implied.

Working with mouse brain and liver cells, as well as embryonic stem cells, Johns Hopkins University School of Medicine professor Andrew Feinberg, M.D., M.P.H., led an investigation of a kind of epigenetic modification to histones, the molecular "spools" that DNA winds around in the cell nucleus. This modification is a variety of the so-called epigenetic changes that alter the function of cells without directly altering the nuclear DNA in the cells.

Other scientists had previously found that histone modifications appear to silence individual genes in the DNA that coils around affected histones. But when Feinberg and his team compared the activity of thousands of genes in the liver and brain cells, they found that a particular modification in which two methyl groups clip onto histones seemed to silence long stretches of DNA containing many genes at once. The findings will publish in Nature Genetics online on Jan. 18.

Since the silenced stretches varied greatly between the different types of cells, Feinberg, postdoctoral fellow Bo Wen, and their colleagues wondered whether these sections called large organized chromatin K9 modifications, or LOCKS might be responsible for the transition from the "blank slate" quality of embryonic cells to the specialized functions that mature cells take on. To find out, he and his team looked for LOCKs in mouse embryonic stem cells. Unlike mature, adult liver and brain cells, in which about 40 percent of the genome was silenced by LOCKs, the embryonic stem cells had no LOCKs.

Next, the researchers compared the regions of DNA affected by LOCKs between mouse liver and brain cells and their corresponding human cel
'/>"/>

Contact: Christen Brownlee
cbrownlee@jhmi.edu
410-955-7832
Johns Hopkins Medical Institutions
Source:Eurekalert

Page: 1 2

Related biology news :

1. Tips for making a green holiday from the worlds largest scientific society
2. Researchers solve piece of large-scale gene silencing mystery
3. Pollution at home lurks unrecognized, instead attributed to large-scale environmental disasters
4. Small satellite takes on large thunderstorms
5. Less than one month to opening of world’s largest global congress on osteoporosis
6. Paradigm Tactical Products to be Largest Distributor of Metal/Radiation Detection Wands in United States
7. Research uncovers new steps on pathway to enlarged heart
8. Yale journal finds nanomaterials may have large environmental footprint
9. Complete Genomics launches, becomes worlds first large-scale human genome sequencing company
10. Lack of large-scale experiments slows progress of environmental restoration
11. Carbon Disclosure Project: Worlds largest corporations seek clarity on climate change regulation
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:12/15/2014)... Dec. 12, 2014 Research and Markets ... of the "Global Facial Recognition Market 2015-2019" ... http://photos.prnewswire.com/prnh/20130307/600769 Facial recognition ... individuals. Facial recognition system measures the overall facial ... edges, mouth, and the distance between eyes. Facial ...
(Date:12/11/2014)... 2014 Research and Markets ... ( http://www.researchandmarkets.com/research/9ql3kr/biometrics_market ) has announced the addition of ... report to their offering. One ... adoption of multimodal biometric systems. Multimodal biometric systems ... for verification and identification purposes. This helps to ...
(Date:12/11/2014)... 10, 2014  Data Sciences International (DSI), the ... a new series of digital telemetry implants to ... M series, part of the PhysioTel™ Digital platform, ... possible physiologic data when incorporating functional endpoints into ... to toxicology studies has evolved from short ECG ...
Breaking Biology News(10 mins):Global Facial Recognition Market 2015-2019: Key Vendors are 3M Cogent, Cognitec Systems, NEC and Safran Group 2Global Facial Recognition Market 2015-2019: Key Vendors are 3M Cogent, Cognitec Systems, NEC and Safran Group 3Biometrics Market in India 2015-2019: Key Vendors are 3M Cogent, NEC, Safran and Suprema 2New telemetry implants expected to change how large animal toxicology studies are conducted 2
... Japan -- In what may prove to be a ... gasses has just become considerably easier. Using a ... Kyoto University,s WPI Institute for Integrated Cell-Material Sciences (iCeMS) ... of low cost, high efficiency separation. The process ...
... MADISON, WI June 22, 2012 Buttery shrimp. Fried ... be a biological reason why fatty and cholesterol-rich foods are ... than 40 years that dietary fat promotes cholesterol uptake, but ... Ph.D., and his colleagues at the Carnegie Institution for Science ...
... asks children who have each been assigned a wetland plant ... other "organisms" their assigned plant or animal interacts with in ... the teacher describes an event that affects one "organism." That ... tug then tug on their strings in turn. The ...
Cached Biology News:Faster, cheaper gas and liquid separation using custom designed and built mesoscopic structures 2Zebrafish research shows how dietary fat regulates cholesterol absorption 2Foundational concept of ecology tested by experiment 2Foundational concept of ecology tested by experiment 3Foundational concept of ecology tested by experiment 4
(Date:12/19/2014)... (PRWEB) December 19, 2014 Bioject ... developer and manufacturer of needle-free injection technology, today ... with Immunomic Therapeutics, Inc. (“ITI”) for ITI to ... with its LAMP™ vaccine platform. , In ... exclusive Worldwide license to the Biojector®-2000 that triggers ...
(Date:12/19/2014)... 2014 Charm Sciences is pleased to ... Detection of Aflatoxin M1 in raw commingled milk is ... party validation. The peer reviewed report of the validation ... for Agricultural and Fisheries Research (ILVO-T&V) has been published ... B1, the most toxic aflatoxin and a known carcinogen, ...
(Date:12/19/2014)... 2014 BioPlus Specialty Pharmacy ... the promotion of Nick Maroulis, Pharm.D. to the newly ... , In this position, Dr. Maroulis will continue ... the directors of our multi-site pharmacies as the company ... and during that time he has served in many ...
(Date:12/19/2014)... Naurex Inc., a biopharmaceutical company leveraging its ... the central nervous system, today announced that Norbert ... present at the 33 rd annual J.P. Morgan ... 3:00 p.m. PST on Tuesday, January 13, 2015, at ... Calif. About Naurex Inc. ...
Breaking Biology Technology:Bioject and Immunomic Therapeutics Enter into an Agreement for License of Needle-Free Technology for LAMP-vax Vaccines 2Bioject and Immunomic Therapeutics Enter into an Agreement for License of Needle-Free Technology for LAMP-vax Vaccines 3Charm Sciences Achieves Independent Validation of First 15 Minute Quantitative Screening Method for Aflatoxin M1 2BioPlus Specialty Pharmacy Promotes Dr. Nick Maroulis to Vice President of Specialty Pharmacy Services 2Naurex to Present at 33rd Annual J.P. Morgan Healthcare Conference 2
... (NYSE: SGP ) is scheduled to announce its sales ... 21, 2009. , , At approximately 7:45 a.m. ... review results for the 2009 second quarter. Fred Hassan, Schering-Plough,s ... conference call. , , To listen live to the ...
... Ind., June 29 Hill-Rom (NYSE: HRC ) ... relating to Negative Pressure Wound Therapy (NPWT) to Kinetic Concepts, ... included U.S. and foreign patents and patent applications covering innovations ... effective immediately. Terms were not disclosed. , , ...
... SAN MATEO, Calif., June 29 NeurogesX, Inc. ... been added to the broad-market Russell 3000(R) and small-cap Russell(R) ... market June 26, 2009 when Russell Investments reconstituted its U.S. ... of Russell,s U.S. indexes captures the 4,000 largest U.S. stocks ...
Cached Biology Technology:Schering-Plough Schedules Conference Call Webcast for 2009 Second Quarter Earnings 2Hill-Rom Announces Sale of Negative Pressure Wound Therapy Intellectual Property 2Hill-Rom Announces Sale of Negative Pressure Wound Therapy Intellectual Property 3NeurogesX Added to Russell 3000 Index 2NeurogesX Added to Russell 3000 Index 3NeurogesX Added to Russell 3000 Index 4
... Goat anti-Human Alpha 1 ... sodium azide Goats were ... Alpha-1-acid glycoprotein in Freund's adjuvant. ... phase absorbed to ensure specificity. ...
Purified Mouse anti-Hu p120 Catenin (pT916) Storage Temperature: Refrigerate(2 to 8C)...
synphilin-1 (V-19)...
Anti-OSMR Monoclonal Antibody Research Focus: cytokine/growth factor Storage: 4C Shipping Temperature: 4C...
Biology Products: