@article{a7bdf9d939d84450a3f161ac8dc91267,
title = "Structural Underpinnings of Nitrogen Regulation by the Prototypical Nitrogen-Responsive Transcriptional Factor NrpR",
abstract = "Plants and microorganisms reduce environmental inorganic nitrogen to ammonium, which then enters various metabolic pathways solely via conversion of 2-oxoglutarate (2OG) to glutamate and glutamine. Cellular 2OG concentrations increase during nitrogen starvation. We recently identified a family of 2OG-sensing proteins-the nitrogen regulatory protein NrpR-that bind DNA and repress transcription of nitrogen assimilation genes. We used X-ray crystallography to determine the structure of NrpR regulatory domain. We identified the NrpR 2OG-binding cleft and show that residues predicted to interact directly with 2OG are conserved among diverse classes of 2OG-binding proteins. We show that high levels of 2OG inhibit NrpRs ability to bind DNA. Electron microscopy analyses document that NrpR adopts different quaternary structures in its inhibited 2OG-bound state compared with its active apo state. Our results indicate that upon 2OG release, NrpR repositions its DNA-binding domains correctly for optimal interaction with DNA thereby enabling gene repression.",
author = "Goragot Wisedchaisri and Dranow, {David M.} and Lie, {Thomas J.} and Bonanno, {Jeffrey B.} and Yury Patskovsky and Ozyurt, {Sinem A.} and Sauder, {J. Michael} and Almo, {Steven C.} and Wasserman, {Stephen R.} and Burley, {Stephen K.} and Leigh, {John A.} and Tamir Gonen",
note = "Funding Information: We thank the Murdock Charitable Trust and the Washington Research Foundation for generous support of our electron cryomicroscopy laboratory. We thank Brian Moore and Abigail Lambert for purification of NrpR protein. We also thank Yifan Cheng (University of California, San Francisco) and Christophe Verlinde (University of Washington) for helpful discussions. This work was funded in part by NIH grant GM-55255 to J.A.L. D.M.D. is supported in part by Public Health Service, National Research Service Award 2T32 GM007270 from the National Institute of General Medical Sciences. The NYSGXRC is supported by NIH Grant U54 GM074945 (Principal Investigator: S.K. Burley). Use of the Advanced Photon Source at Argonne National Laboratory was supported by the U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. Use of the Lilly Research Laboratories Collaborative Access Team (LRL-CAT) beamline at Sector 31 of the Advanced Photon Source was provided by Eli Lilly & Company, which operates the facility. We gratefully acknowledge the contributions of all NYSGXRC personnel. T.G. is a Howard Hughes Medical Institute Early Career Scientist. The authors declare no competing financial interests. ",
year = "2010",
month = nov,
day = "10",
doi = "10.1016/j.str.2010.08.014",
language = "English (US)",
volume = "18",
pages = "1512--1521",
journal = "Structure with Folding & design",
issn = "0969-2126",
publisher = "Cell Press",
number = "11",
}