Home > Group Leaders > X to Y
 

Pingyong Xu, Ph.D, Prof.

Principal Investigator
Key laboratory of RNA Biology, IBP, CAS
Genetically encoded probes and small molecular chemical probes
Regulation mechanism of glucose metabolism by neurons
Functional study of the relationship between autophagy and diabetes.
E-mail:pyxu@ibp.ac.cn,Tel:010-64888808
Fax:010-64888524,Zip code:100101

Biography & Introduction

1992-1996 Central China Normal University, B.S. in Chemical Education, Wuhan, China

1996-2000 Central China Normal University, M.S. in Organic Chemistry, Wuhan, China

2000-2004 Huazhong University of Science and Technology, Ph.D. in Engineering of Biomedicine, Wuhan, China

2004 - 2006 Postdoctoral Fellow, Assistant Professor,Institute of Biophysics, Chinese Academy of Sciences, Beijing, China

2006 - 2010 Associate Professor, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China

2010 - Professor, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China

Awards

2008 The State Natural Science Award (the second class), P.R.CHINA

2009 Lu Jiaxi Young Talent Award from Chinese Academy of Sciences

Research Interest

Our studies focus on two aspects: one combines spectroscopy, biophysical microscopy techniques, and protein design and engineering for the development of novel optical imaging tools, especially photocontrollable fluorescent proteins and functional chemical dyes. In addition, our research uses the probes we develop in SR techniques to study important biological processes such as autophagosome formation.

Using fluorescence microscopy, information about the spatial organization of specific target proteins can be accurately provided at the molecular level by labeling proteins with fluorescent proteins. However, conventional optical microscopy is limited by diffraction to imaging on a coarser scale (~250 nm) by two orders of magnitude. Recently, several SR imaging techniques, such as single molecule localization-based microscopy (PALM/FPALM/STORM) and structured illumination-based techniques such as nonlinear structured illumination microscopy (NL-SIM), were developed for the study of cellular ultrastructure at diffraction-unlimited resolutions. However, many efforts are still needed to improve the spatial and temporal resolutions and labeling technology, especially in living cells. One of the major limits is the absence of appropriate fluorescent probes with specific photochemical properties. Different SR techniques use different fluorescent probes with optimized properties. Live-cell SR imaging is also very challenging because it requires fluorescent proteins to be very stable and bright and have a high contrast ratio. We mainly focus on developing novel fluorescent probes, especially fluorescent proteins that show priority to dyes in living cells, for diffraction-unlimited optical microscopy. We hope to further improve the spatial-temporal resolution using multiple fluorescent labels with higher photon numbers and contrast ratios.

Although many current SR techniques have been successfully demonstrated to image cellular dynamics, applications have been rather limited and appear challenging. Live-cell STED/reversible saturable optical fluorescence transition (RESOLFT) and SIM/nonlinear SIM require sophisticated and expensive optical setups and professional expertise for accurate optical alignment. Live-cell PALM/STORM uses a less complicated setup; however, a sCMOS camera, whose pixel-dependent noise should be pre-characterized and calibrated before use, is required for extremely high acquisition speeds over tens of thousands of frames. Recently, wide-field based SR microscopies have been developed to improve temporal resolution using much fewer time-lapse images (hundreds to thousands) than PALM/STORM. One of them, a Bayesian analysis of blinking and bleaching (3B), offers enormous potential to resolve ultrastructure and fast cellular dynamics beyond the diffraction limit in living cells. Despite the potential, the 3B analysis is impractical when imaging the nanoscale dynamics of large fields of view in live cells over long time periods, as the calculation is extremely time-consuming and/or consumes large amounts of web resources. Another major problem for 3B imaging is the artificial thinning and thickening of structures both in simulated images and experimental data. Our goal is to develop simple but useful SR techniques with high spatial-temporal resolution. We are developing novel algorithms and imaging techniques based on a simple TIRFM system to make them useful SR imaging tools in common labs for both fixed and living cells.

At present, the research on localization and related functions of proteins using super-resolution imaging techniques in the field of neuroscience is still at an early stage. Probes and methods for characterizing neuronal activity are yet to be further developed. Our group will take advantage of our expertise in fluorescent protein engineering and methods to develop novel probes and methods for characterizing neuronal activity and to investigate the localization and function usingsuper-resolution imaging techniques in neurons.

Selected Publication

1. Yuan L, Wang H, Liu Q, Wang Z, Zhang M, Zhao Y, Liang K, Chen L, Xu T*, Xu P*. Etoposide-induced protein 2.4 functions as a regulator of the calcium ATPase and protects pancreatic β cell survival[J]. Journal of Biological Chemistry, 2018: jbc. RA118. 002399.

2. Xue F, He W, Xu F, Zhang M, Chen L, Xu P*. Hessian single-molecule localization microscopy using sCMOS camera[J]. Biophysics reports, 2018, 4(4): 215-221.

3. Liu Q, Xu P, Yuan L*. A Method for Identifying The Topology of Etoposide - induced Protein 2.4 Using Split mNeonGreen2[J]. Progress in Biochemistry and Biophysics, 2018, 45(12): 1280-1287.

4. Xu F, Zhang M, He W, Han R, Xue F, Liu Z, Zhang F*, Lippincott-Schwartz J*, Xu P*, Live-cell single molecule-guided Bayesian localization super-resolution microscopy. Cell Research. 2016 Dec 30.doi: 10.1038/cr.2015.160.

5. Zhang X, Zhang M, Li D, He W, Peng J, Betzig E*, Xu P*. Highly photostable, reversibly photoswitchable fluorescent protein with high contrast ratio for live-cell superresolution microscopy. Proc Natl Acad Sci U S A. 2016 Sep 13;113(37):10364-9.

6. Du W, Zhou M, Zhao W, Cheng D, Wang L, Lu J, Song E, Feng W, Xue Y*, Xu P*, Xu T*. HID-1 is required for homotypic fusion of immature secretory granules during maturation. Elife. 2016 Oct 18;5. pii: e18134. doi: 10.7554/eLife.18134.

7. Zhang X, Chen X, Zeng Z, Zhang M, Sun Y, Xi P*, Peng J*, Xu P*. Development of a reversibly switchable fluorescent protein for super-resolution optical fluctuation imaging (SOFI). ACS Nano. 2015 Mar 24;9(3):2659-67.

8. Chen J, Jing J, Chang H, Rong Y, Hai Y, Tang J, Zhang J* and Xu P*. A sensitive and quantitative autolysosome probe for detecting autophagic activity in live and prestained fixed cells. Autophagy, 2013 Apr 10;9(6).

9. Jing J, Chen J, Hai Y, Zhan J, Xu P* and Zhang J*. Rational Design of ZnSalen as a Single and Two Photon Activatable Fluorophore in Living Cells. Chemical Science. 2012, 3(11):3315-9.

10. Mingshu Zhang, Hao Chang, Yongdeng Zhang, Yu J, Wu L, Ji W, Chen J, Liu B, Lu J, Liu Y, Zhang J, Xu P*, Xu T*. (2012) Rational design of true monomeric and bright photoactivatable fluorescent proteins. Nature Methods 9(7), 727-9.

11. Chang H, Zhang M, Ji W, Chen J, Zhang Y, Liu B, Lu J, Zhang J, Xu P*, Xu T*. (2012) A unique series of reversibly switchable fluorescent proteins with beneficial properties for various applications. Proc Natl Acad Sci U S A. 109(12), 4455-60.

12. Hai Y, Chen JJ, Zhao P, Lv H, Yu Y, Xu P*, Zhang JL*. Luminescent zinc salen complexes as single and two-photon fluorescence subcellular imaging probes. ChemCommun (Camb). 2011 Feb 28;47(8):2435-7.  

13. Ji W, Xu P, Li Z, Lu J, Liu L, Zhan Y, Chen Y, Hille B, Xu T, Chen L. Functional stoichiometry of the unitary calcium-release-activated calcium channel. Proc Natl Acad Sci U S A. 2008 Sep 9;105(36):13668-73. (Pingyong Xu as co-first author)

14. Bai L, Wang Y, Fan J, Chen Y, Ji W, Qu A, Xu P*, James DE, Xu T*. Dissecting Multiple Steps of GLUT4 Trafficking and Identifying the Sites of Insulin Action. Cell Metab. 2007 Jan;5(1):47-57.

15. Xu P, Lu J, Li Z, Yu X, Chen L, Xu T. Aggregation of STIM1 underneath the plasma membrane induces clustering of Orai1. Biochem Biophys Res Commun. 2006 Dec 1;350(4):969-76.

 

 

From Pingyong Xu, 2019-01-30 update

Print Text Size: A A A   Close

 


Institute of Biophysics, CAS    Address: 15 Datun Road, Chaoyang District, Beijing, 100101, China
Tel:8610-64889872    Fax: 8610-64871293    E-mail: office@ibp.ac.cn