To the top

Page Manager: Webmaster
Last update: 9/11/2012 3:13 PM

Tell a friend about this page
Print version

Protein sliding and DNA d… - University of Gothenburg, Sweden Till startsida
To content Read more about how we use cookies on

Protein sliding and DNA denaturation are essential for DNA organization by human mitochondrial transcription factor A

Journal article
Authors G. Farge
N. Laurens
O. D. Broekmans
Smjl van den Wildenberg
L. C. M. Dekker
M. Gaspari
Claes M Gustafsson
E. J. G. Peterman
Maria Falkenberg
G. J. L. Wuite
Published in Nature Communications
Volume 3
ISSN 2041-1723
Publication year 2012
Published at Institute of Biomedicine, Department of Medical Biochemistry and Cell Biology
Language en
Keywords factor-a, bacterial chromatin, architectural role, optical tweezers, binding, tension, microscopy, nucleoids, diffusion, reveals, ghee jd, 1974, journal of molecular biology, v86, p469
Subject categories Medical Biotechnology


Mitochondria organize their genome in protein-DNA complexes called nucleoids. The mitochondrial transcription factor A (TFAM), a protein that regulates mitochondrial transcription, is abundant in these nucleoids. TFAM is believed to be essential for mitochondrial DNA compaction, yet the exact mechanism has not been resolved. Here we use a combination of single-molecule manipulation and fluorescence microscopy to show the nonspecific DNA-binding dynamics and compaction by TFAM. We observe that single TFAM proteins diffuse extensively over DNA (sliding) and, by collisions, form patches on DNA in a cooperative manner. Moreover, we demonstrate that TFAM induces compaction by changing the flexibility of the DNA, which can be explained by local denaturation of the DNA (melting). Both sliding of TFAM and DNA melting are also necessary characteristics for effective, specific transcription regulation by TFAM. This apparent connection between transcription and DNA organization clarifies how TFAM can accomplish two complementary roles in the mitochondrial nucleoid at the same time.

Page Manager: Webmaster|Last update: 9/11/2012

The University of Gothenburg uses cookies to provide you with the best possible user experience. By continuing on this website, you approve of our use of cookies.  What are cookies?