This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. After HIV infects a cell and a reverse transcribed copy of its RNA genome has integrated into the host genome, generation of viral RNAs requires the transactivation activity of a viral protein, Tat, in conjunction with the host's P-TEFb. Tat and the specific form of P-TEFb that contains Cdk9 and cyclin T1 bind to a stem and loop structure (TAR) in the 5?R end of the nascent HIV transcript. Recruitment of P-TEFb in this way promotes the transition of engaged polymerases at the HIV LTR into productive elongation. This recruitment mechanism initially seemed bizarre, and TAR still represents perhaps the only example of a eukaryotic """"""""RNA enhancer"""""""". However, the recent discovery of the P-TEFb regulatory machinery provides evidence that HIV took advantage not only of P-TEFb, but the whole P-TEFb control process. There are significant similarities between the Tat-TAR-P-TEFb complex and the HEXIM-7Sk-P-TEFb complex. Indeed, the RNA binding domain of Tat will functionally substitute for the RNA binding domain of HEXIM1 in a chimeric HEXIM1-Tat protein. The main difference between the two P-TEFb complexes is that HEXIM1 and 7SK inhibit P-TEFb, while Tat and TAR do not. Understanding the details of the Tat-TAR-P-TEFb complex afforded by the proposed structural studies may provide rational targets for small molecules to block the complex formation and, thereby, inhibit HIV replication. All general P-TEFb inhibitors, including Flavopiridol, block HIV replication, but at slightly higher concentrations also exhibit cellular toxicity. Molecules that block the formation of the Tat-TAR-P-TEFb complex would likely be more specific for HIV transcription than general P-TEFb inhibitors.
The aim of this proposal is to solve the structures of Tat-P-TEFb,Tat-TAR-P-TEFb and HEXIM-7Sk-P-TEFb complexes.

Agency
National Institute of Health (NIH)
Institute
National Center for Research Resources (NCRR)
Type
Biotechnology Resource Grants (P41)
Project #
5P41RR015301-09
Application #
8361646
Study Section
Special Emphasis Panel (ZRG1-BCMB-K (40))
Project Start
2011-04-01
Project End
2012-03-31
Budget Start
2011-04-01
Budget End
2012-03-31
Support Year
9
Fiscal Year
2011
Total Cost
$15,112
Indirect Cost
Name
Cornell University
Department
Chemistry
Type
Schools of Arts and Sciences
DUNS #
872612445
City
Ithaca
State
NY
Country
United States
Zip Code
14850
Chen, Wenyang; Mandali, Sridhar; Hancock, Stephen P et al. (2018) Multiple serine transposase dimers assemble the transposon-end synaptic complex during IS607-family transposition. Elife 7:
Eichhorn, Catherine D; Yang, Yuan; Repeta, Lucas et al. (2018) Structural basis for recognition of human 7SK long noncoding RNA by the La-related protein Larp7. Proc Natl Acad Sci U S A 115:E6457-E6466
Fallas, Jorge A; Ueda, George; Sheffler, William et al. (2017) Computational design of self-assembling cyclic protein homo-oligomers. Nat Chem 9:353-360
Krotee, Pascal; Rodriguez, Jose A; Sawaya, Michael R et al. (2017) Atomic structures of fibrillar segments of hIAPP suggest tightly mated ?-sheets are important for cytotoxicity. Elife 6:
Dhayalan, Balamurugan; Mandal, Kalyaneswar; Rege, Nischay et al. (2017) Scope and Limitations of Fmoc Chemistry SPPS-Based Approaches to the Total Synthesis of Insulin Lispro via Ester Insulin. Chemistry 23:1709-1716
Bale, Jacob B; Gonen, Shane; Liu, Yuxi et al. (2016) Accurate design of megadalton-scale two-component icosahedral protein complexes. Science 353:389-94
AhYoung, Andrew P; Koehl, Antoine; Vizcarra, Christina L et al. (2016) Structure of a putative ClpS N-end rule adaptor protein from the malaria pathogen Plasmodium falciparum. Protein Sci 25:689-701
Hancock, Stephen P; Stella, Stefano; Cascio, Duilio et al. (2016) DNA Sequence Determinants Controlling Affinity, Stability and Shape of DNA Complexes Bound by the Nucleoid Protein Fis. PLoS One 11:e0150189
Kattke, Michele D; Chan, Albert H; Duong, Andrew et al. (2016) Crystal Structure of the Streptomyces coelicolor Sortase E1 Transpeptidase Provides Insight into the Binding Mode of the Novel Class E Sorting Signal. PLoS One 11:e0167763
Jorda, J; Leibly, D J; Thompson, M C et al. (2016) Structure of a novel 13 nm dodecahedral nanocage assembled from a redesigned bacterial microcompartment shell protein. Chem Commun (Camb) 52:5041-4

Showing the most recent 10 out of 407 publications