Navigation Links
UM scientists demonstrate role of RNA polymerase in gene transcription

In all organisms, RNA synthesis is carried out by proteins known as RNA polymerases (RNAPs) that transcribe the genetic information from DNA in a highly-regulated, multi-stage process. RNAP is the key enzyme involved in creating an equivalent RNA copy of a sequence of DNA. This transcription is the first step leading to gene expression. While the major steps in RNA synthesis have been known for several decades, scientists have only recently begun to decipher the detailed molecular steps of the complex transcription process.

In research published in the July 1, 2010 online Early Edition of the Proceedings of the National Academy of Sciences, University of Maryland biophysicists Devarajan (Dave) Thirumalai and Jie Chen, along with Rockefeller University collaborator Seth Darst, provide new insight into how the transcription process is initiated and the role that RNA polymerase plays in making this happen. Because the sequence, structure, and function of multi-subunit RNA polymerase are universally conserved in all organisms -- from bacteria to humans -- understanding the mechanisms of bacterial gene transcription is an important step in deciphering the role of genetics in disease.

"Previously, people didn't know the precise role of RNA polymerase in initiating transcription," explains Distinguished University Professor Dave Thirumalai (Department of Chemistry and Biochemistry and Institute for Physical Science and Technology), "but we showed that it plays an important role in forming the transcription bubble and in the process of bending the DNA to facilitate entry of DNA into the active site. That is the process we described computationally."

Their simulation of the initiation phase of transcription in bacterial RNA polymerase showed a three-step process. It begins when the RNA polymerase binds with transcription promoting regions of DNA. Through interactions with the RNA polymerase, the DNA helix then unwinds, forming an open "bubble" that allows the polymerase access to the exposed DNA sequence to begin transcription. The DNA molecule then bends to relieve stress produced by the opening.

Dr. Jie Chen, who conducted this research while a graduate student in the Chemical Physics program, simulated the transcription bubble formation using a Brownian dynamics-based computer model developed by Dr. Thirumalai's laboratory. "By creating this molecular movie, we can look at the dynamics of RNAP and simulate how it shifts from one structure to another structure," explains Chen. "Our simulation confirms experimental observations, and goes further to establish a clear and active role for RNA polymerase."

Dr. Thirumalai's research group is continuing to study RNA polymerase by looking at the second phase of the transcription process in bacteria and also through models of human transcription.


Contact: Kelly Blake
University of Maryland

Related biology news :

1. Scientists identify new potential biocontrol for skunk vine
2. A*STAR scientists score hat-trick against cancer
3. Scientists use computer algorithms to develop seasonal flu vaccines
4. Damon Runyon Cancer Research Foundation awards prestigious fellowships to 18 top young scientists
5. PNNL scientists win 4 R&D 100 awards for environment, biology, security technologies
6. Scientists describe 2 new species of fish from area engulfed by oil spill
7. Marine scientists return with rare creatures from the deep
8. Scientists find direct line from development to growth
9. UM School of Medicine scientists develop new strategy that may improve cognition
10. Honey as an antibiotic: Scientists identify a secret ingredient in honey that kills bacteria
11. NOAA-supported scientists predict larger than average Gulf dead zone
Post Your Comments:
(Date:11/9/2015)... 09, 2015 ... the "Global Law Enforcement Biometrics Market ... --> ) has announced the ... Biometrics Market 2015-2019" report to their ... ( ) has announced the addition ...
(Date:10/29/2015)...   MedNet Solutions , an innovative SaaS-based eClinical ... research, is pleased to announce that it has been ... one of only three finalists for a 2015 ... Growing" category. The Tekne Awards honor Minnesota ... innovation and leadership. iMedNet™ eClinical ...
(Date:10/29/2015)... Oct. 29, 2015  Connected health pioneer, Joseph ... explosion of technology-enabled health and wellness, and the business ... The Internet of Healthy Things . ... smartphones even existed, Dr. Kvedar, vice president, Connected Health, ... care delivery, moving care from the hospital or doctor,s ...
Breaking Biology News(10 mins):
(Date:11/24/2015)... --> --> ... by Transparency Market Research, the global non-invasive prenatal testing ... 17.5% during the period between 2014 and 2022. The ... Analysis, Size, Volume, Share, Growth, Trends and Forecast 2014 ... to reach a valuation of US$2.38 bn by 2022. ...
(Date:11/24/2015)... ... November 24, 2015 , ... In harsh industrial ... points for in-line sensors can represent a weak spot where leaking process media ... of retractable sensor housings , which are designed to tolerate extreme process conditions. ...
(Date:11/24/2015)... LOS ANGELES , Nov. 24, 2015 ... a biotechnology company focused on the discovery, development and ... Marban , Ph.D., Chief Executive Officer, is scheduled to ... December 1, 2015 at 10:50 a.m. EST, at The ... York City . . ...
(Date:11/24/2015)... ... , ... Whitehouse Laboratories is pleased to announce that it has completed construction ... dedicated to basic USP 61, USP 62 and USP 51 testing specific to raw ... and micro testing performed by one supplier. Management has formally announced that ...
Breaking Biology Technology: