4L5G

Crystal structure of Thermus thermophilus CarD

Summary for 4L5G

• Entry DOI: 10.2210/pdb4l5g/pdb
• Descriptor: CarD (2 entities in total)
• Functional Keywords: transcription regulator, rna polymerase, transcription
• Biological source: Thermus thermophilus
• Total number of polymer chains: 2
• Total formula weight: 37087.56

Authors

Srivastava, D.B.,Westblade, L.F.,Campbell, E.A.,Darst, S.A. (deposition date: 2013-06-11, release date: 2013-07-31, Last modification date: 2024-11-27)

Primary citation

Srivastava, D.B.,Leon, K.,Osmundson, J.,Garner, A.L.,Weiss, L.A.,Westblade, L.F.,Glickman, M.S.,Landick, R.,Darst, S.A.,Stallings, C.L.,Campbell, E.A.
Structure and function of CarD, an essential mycobacterial transcription factor.
Proc.Natl.Acad.Sci.USA, 110:12619-12624, 2013

PubMed Abstract: CarD, an essential transcription regulator in Mycobacterium tuberculosis, directly interacts with the RNA polymerase (RNAP). We used a combination of in vivo and in vitro approaches to establish that CarD is a global regulator that stimulates the formation of RNAP-holoenzyme open promoter (RPo) complexes. We determined the X-ray crystal structure of Thermus thermophilus CarD, allowing us to generate a structural model of the CarD/RPo complex. On the basis of our structural and functional analyses, we propose that CarD functions by forming protein/protein and protein/DNA interactions that bridge the RNAP to the promoter DNA. CarD appears poised to interact with a DNA structure uniquely presented by the RPo: the splayed minor groove at the double-stranded/single-stranded DNA junction at the upstream edge of the transcription bubble. Thus, CarD uses an unusual mechanism for regulating transcription, sensing the DNA conformation where transcription bubble formation initiates.

PubMed: 23858468
DOI: 10.1073/pnas.1308270110

Experimental method

X-RAY DIFFRACTION (2.3902 Å)