Shasha Chong

Assistant Professor of Chemistry; Ronald and JoAnne Willens Scholar

B.S. University of Science & Technology of China, 2008; Ph.D. Harvard University, 2014.

Research Summary

Transcription; intrinsically disordered regions; single-molecule imaging and biophysics; cancer biology

Profile

Research in the Chong lab interfaces between chemistry, physics, and biology to tackle the molecular mechanisms of fundamental cellular processes. We are interested in intrinsically disordered regions, which compose nearly half of the eukaryotic proteome and perform critical functions in numerous cellular processes without forming stable protein structures. Primary goals of our research include 1) understanding the fundamental rules that govern the interaction behaviors of intrinsically disordered regions and 2) elucidating their roles in regulating gene transcription under normal and disease conditions, including cancer and diabetes.

Biomolecular transactions are often highly dynamic, reversible, and heterogeneous. An in-depth mechanistic understanding of them requires visualizing biomolecules one at a time with high spatiotemporal resolution under physiological conditions. To this end, we will develop novel live-cell and in vitro single-molecule imaging methods and combine them with genome editing, biochemical, genomic, proteomic, and bioinformatic approaches in our research.

Irgen-Gioro, S.; Walling, V.; Chong, S.† (2022) "Fixation can change the appearance of phase separation in living cells" BioRxiv, 2022.05.06.490956

Chong, S.; Graham, T. G. W.; Dugast-Darzacq, C.; Dailey, G. M.; Darzacq, X.; Tjian, R. (2022) "Tuning levels of low-complexity domain interactions to modulate endogenous oncogenic transcription" Molecular Cell, 82, 1-14.

Seong, B. K.; Dharia, N. V.; Lin, S.; Donovan, K. A.; Chong, S.; Robichaud, A.; Conway, A.; Hamze, A.; Ross, L.; Adane, B.; Nabet, B.; Ferguson, F.; Stolte, B.; Wang, E. J.; Sun, J.; Darzacq, X.; Piccioni, F.; Gray, N. S.; Fischer, E. S.; Stegmaier, K. (2021) "TRIM8 Modulates the EWS/FLI1 Oncoprotein to Promote Survival in Ewing Sarcoma" Cancer Cell, 39, 1262-1278.

Chong, S.†; Mir, M. (2021) "Toward Decoding the Sequence-Based Grammar Governing the Functions of Intrinsically Disordered Protein Regions" J. Mol. Biol. 433, 166724.

Esbin, M. N.; Whitney, O. N.; Chong, S.; Maurer, A.; Darzacq, X.; Tjian, R. (2020) "Overcoming the Bottleneck to Widespread Testing: A Rapid Review of Nucleic Acid Testing Approaches for COVID-19 Detection" RNA, 26, 771-783.

Wan, L.; Chong, S.*; Xuan, F.*; Liang, A.*; Cui, X.; Gates, L.; Carroll, T.; Li, Y.; Feng, L.; Chen, G.; Wang, S.-P.; Ortiz, M.; Daley, S.; Wang, X.; Xuan, H.; Kentsis, A.; Muir, T.; Roeder, R. G.; Li, H.; Li, W.; Tjian, R.; Wen, H.; Allis, C. D. (2020) "Impaired Cell Fate by Gain-of-Function Mutations in a Chromatin Reader" Nature, 577, 121-126.

Chong, S.; Dugast-Darzacq, C.; Liu, Z.; Dong, P.; Dailey, G. M.; Cattoglio, C.; Heckert, A.; Banala, S.; Lavis, L.; Darzacq, X.; Tjian, R. (2018) "Imaging Dynamic and Selective Low-Complexity Domain Interactions That Control Gene Transcription" Science, 361, eaar2555.

Chong, S.*; Chen, C.*; Ge, H.; Xie, X. S. (2014) "Mechanism of Transcriptional Bursting in Bacteria" Cell, 158, 314-326.

Kim, S.*; Broströmer, E.*; Xing, D.*; Jin, J.*; Chong, S.; Ge, H.; Wang, S.; Gu, C.; Yang, L.; Gao, Y. Q.; Su, X.; Sun, Y.; Xie, X. S. (2013) "Probing Allostery Through DNA" Science, 339, 816-819.

Chong, S.*; Min, W.* & Xie, X. S. (2010) "Ground-State Depletion Microscopy: Detection Sensitivity of Single-Molecule Optical Absorption at Room Temperature" J. Phys. Chem. Lett., 1, 3316-3322.

Lu, S.*; Min, W.*; Chong, S.; Holtom, G. R. & Xie, X. S. (2010) "Label-free Imaging of Heme Proteins with Two-photon Excited Photothermal Lens Microscopy" Appl. Phys. Lett., 96, 113701.

Min, W.*; Lu, S.*; Chong, S.; Roy, R.; Holtom, G. R. & Xie, X. S. (2009) "Imaging Chromophores with Undetectable Fluorescence by Stimulated Emission Microscopy" Nature, 461, 1105-1109.

Fu, Y.; Wang, H.-J.; Chong, S.; Guo, Q.-X. & Liu, L. (2009) "An Extensive Ylide Thermodynamic Stability Scale Predicted by First-Principle Calculation" J. Org. Chem., 74, 810-819.

Shi, J.; Chong, S.; Fu, Y.; Liu, L. & Guo, Q.-X. (2008) "Ring Opening versus Ring Expansion in Rearrangement of Bicyclic Cyclobutylcarbinyl Radicals" J. Org. Chem., 73, 974-982.

Chong, S.; Fu, Y.; Liu, L. & Guo, Q.-X. (2007) "O-H Bond Dissociation Enthalpies of Oximes: A Theoretical Assessment and Experimental Implications" J. Phys. Chem. A, 111, 13112-13125.

(*These authors contributed equally; †Corresponding author)

BMB/Bi/Ch 174. Advanced Topics in Biochemistry and Molecular Biophysics. 6 units (3-0-3); first term, 2022-23. Prerequisites: Ch/Bi 110 or equivalent. Discussion of research fields in biochemistry and molecular biophysics at Caltech. Development of skills in literature analysis and information synthesis.
Instructors: Chong, Semlow, and guest lecturers

Assistant Professor of Chemistry; Ronald and JoAnne Willens Scholar

Publications