Zhen-Qiang Pan, PhD
img_Zhen-Qiang Pan
PROFESSOR | Oncological Sciences
Research Topics
Cancer, Enzymology, Protein Degradation, Signal Transduction
Multi-Disciplinary Training Area
Cancer Biology [CAB]
Ubiquitin Signaling in Cancer Biology

Post-doctoral Fellow: Kenneth Wu 

MD/PhD Graduate Student: Robert A. Chong

Covalent linkage of ubiquitin chains to cellular proteins leads to targeted substrate degradation by the 26S proteasome, thereby promoting unidirectional alteration of a divergent array of cellular processes, such as cell cycle progression and signal transduction, in a manner that profoundly impacts tumorigenesis.

Central to the ubiquitination reaction is the recognition of a substrate by an E3 ubiquitin protein ligase, which also functions to recruit an E2 ubiquitin-conjugating enzyme that catalyzes the transfer of ubiquitin to the target protein. Work from this laboratory has helped discover and characterize a super-family of E3s known as the cullin-RING ubiquitin ligases (CRL). CRL comprises ~300 modular protein complexes (including CRL1/SCF, CRL2-5 and CRL7), nearly half of E3s in humans. Lysine 48 (K48)-polyubiquitination mediated by CRL is a predominant cellular mechanism for targeting proteins for degradation by the 26S proteasome. CRL deregulation causes protein imbalance that contributes to myriad cellular defects or disease states such as cancer.


To understand and target K48 polyubiquitination by CRL, we recently developed fluorescence (Förster) resonance energy transfer (FRET)-based cell free reporter systems that generate a specific fluorescence signal as a result of enzymatic synthesis of an ubiquitin-ubiquitin covalent linkage through K48. On the basis of this assay format, we have performed high throughput screens, resulting in identification of a diversified array of small molecule inhibitors and are currently exploring their mechanisms of action and therapeutic potentials.


In addition, fluorescence-based assays are highly sensitive, allowing direct visualization of the process of K48 ubiquitination.  We are exploring this innovation to develop real time reaction models that help understand the dynamics of K48 ubiquitination, a process of fundamental importance to a living cell.

The Pan Laboratoroy

PhD, Columbia University

Physicians and scientists on the faculty of the Icahn School of Medicine at Mount Sinai often interact with pharmaceutical, device and biotechnology companies to improve patient care, develop new therapies and achieve scientific breakthroughs. In order to promote an ethical and transparent environment for conducting research, providing clinical care and teaching, Mount Sinai requires that salaried faculty inform the School of their relationships with such companies.

Dr. Pan did not report having any of the following types of financial relationships with industry during 2022 and/or 2023: consulting, scientific advisory board, industry-sponsored lectures, service on Board of Directors, participation on industry-sponsored committees, equity ownership valued at greater than 5% of a publicly traded company or any value in a privately held company. Please note that this information may differ from information posted on corporate sites due to timing or classification differences.

Mount Sinai's faculty policies relating to faculty collaboration with industry are posted on our website. Patients may wish to ask their physician about the activities they perform for companies.