Nuclear Receptor
The Wang Lab first uses electron cryo-microscopy (Cryo-EM) to determine the structural architecture of DNA-bound ER-alpha, SRC-3, and a secondary coactivator (p300) complex. This work provides a structural basis for understanding the assembly of a transcriptionally active nuclear receptor-coactivator complex. In a continuing study, we developed a computational procedure to classify the images in order to sort out different assembly of 3D structures. We demonstrated that a late-recruited coactivator alters the structure and function of the pre-existing receptor-coactivator complex to synergistically activate estrogen receptor-mediated transcription and to prepare the complex for the next step of transcription.
Our latest study determines the first structure of DNA bound androgen receptor and the active androgen receptor-coactivator complex binding with the same core activators (SRC-3 and p300). Our work highlights the N-terminal direct involvement in the coactivator recruitment and provide a structural basis on the understanding difference between estrogen receptor-mediated and androgen receptor-mediated transcriptional activation.
Related Publications:
Yi P, Wang Z, Feng Q, Pintilie GD, Foulds CE, Lanz RB, Ludtke SJ, Schmid MF, Chiu W, O'Malley BW. Structure of a biologically active estrogen receptor-coactivator complex on DNA. Mol Cell. 2015 Mar 19;57(6):1047-1058. PubMed Central ID: PMC4369429.
Yi P, Wang Z, Feng Q, Chou CK, Pintilie GD, Shen H, Foulds CE, Fan G, Serysheva I, Ludtke SJ, Schmid MF, Hung MC, Chiu W, O'Malley BW. Structural and Functional Impacts of ER Coactivator Sequential Recruitment. Mol Cell. 2017 Sep 7;67(5):733-743.e4. PubMed Central ID: PMC5657569.
Yu X, Yi P, Hamilton RA, Shen H, Chen M, Foulds CE, Mancini MA, Ludtke SJ, Wang Z, O'Malley BW. Structural Insights of Transcriptionally Active, Full-Length Androgen Receptor Coactivator Complexes. Mol Cell. 2020 Sep 3;79(5):812-823.e4. PubMed Central ID: PMC7483370.
Yi P, Yu X, Wang Z, O'Malley BW. Steroid receptor-coregulator transcriptional complexes: new insights from CryoEM. Essays Biochem. 2021 Dec 17;65(6):857-866. PubMed ID: 34061186.
Multidrug Efflux Pump (in vivo/vitro)
Research on assembling and working mechanisms of multidrug efflux pump from bacteria is the most enduring project in my research, spanning the last decade. Expression of the efflux pump is one the major reason causes antibiotic resistance in pathogenic bacteria and it is known as an important drug target. Utilizing recent technological advances in direct electron detection and advances in image processing algorithms, we have solved the first in-vitro structure of the entire efflux pump reveal the assembly architecture of the complex in substrate-free to at 16 Å by single-particle cryo-EM, into which crystallographic structures of individual components could be docked. We have now improved the resolution of this pump to 3.9 Å resolution and solved a number of functional states with substrate binding by single-particle cryo-EM. This new view of the detailed interactions of the components confirms some past proposals and adds fascinating new information for the first time.
Our laboratory is a pioneer in investigating the in-vivo structure of the efflux pump directly solve in living bacteria using cryoET and our current research efforts are focused on technical development to push higher resolution beyond the current limit. Our newly published in-situ structures resolve key questions concerning stoichiometry in the complete structure and offer new insights into the assembly and operation of important determinants of drug resistance that are conserved in a wide range of pathogens.
Related Publications
Du D, Wang Z, James NR, Voss JE, Klimont E, Ohene-Agyei T, Venter H, Chiu W, Luisi BF. Structure of the AcrAB-TolC multidrug efflux pump. Nature. 2014 May 22;509(7501):512-5. PubMed Central ID: PMC4361902.
Shi X, Chen M, Yu Z, Bell JM, Wang H, Forrester I, Villarreal H, Jakana J, Du D, Luisi BF, Ludtke SJ, Wang Z. In situ structure and assembly of the multidrug efflux pump AcrAB-TolC. Nat Commun. 2019 Jun 14;10(1):2635. PubMed Central ID: PMC6570770.
Chen M, Bell JM, Shi X, Sun SY, Wang Z, Ludtke SJ. A complete data processing workflow for cryo-ET and subtomogram averaging. Nat Methods. 2019 Nov;16(11):1161-1168. PubMed Central ID: PMC6858567.
Chen M, Shi X, Yu Z, Fan G, Serysheva II, Baker ML, Luisi BF, Ludtke SJ, Wang Z. In situ structure of the AcrAB-TolC efflux pump at subnanometer resolution. Structure. 2022 Jan 6;30(1):107-113.e3. PubMed Central ID: PMC8741639.
Damage Compensation and DDD Data Process
We are interested development of experimental methodologies for the structural determination of biological assemblies by single-particle cryo-electron microscopy (cryo-EM) towards atomic resolution. My research includes developing experimental methodologies of the first-generation direct electron detection device (DDD) and first solving a high-resolution structure using a small plant virus. My strategy, a novel protocol of data collation and processing includes the first development of the "damage compensation" analysis strategy, is now commonly used in the EM community. In the last decade, the achievement of near-atomic resolution (<4 Å) has attracted wide attention to the approach. I am the first one to push the resolution beyond 4Å using a DDD camera (DE).
Related Publications
Hryc CF, Chen DH, Afonine PV, Jakana J, Wang Z, Haase-Pettingell C, Jiang W, Adams PD, King JA, Schmid MF, Chiu W. Accurate model annotation of a near-atomic resolution cryo-EM map. Proc Natl Acad Sci U S A. 2017 Mar 21;114(12):3103-3108. PubMed Central ID: PMC5373346.
Wang Z, Hryc CF, Bammes B, Afonine PV, Jakana J, Chen DH, Liu X, Baker ML, Kao C, Ludtke SJ, Schmid MF, Adams PD, Chiu W. An atomic model of brome mosaic virus using direct electron detection and real-space optimization. Nat Commun. 2014 Sep 4;5:4808. PubMed Central ID: PMC4155512.