Vivian W Tang

Vivian W Tang

vtang@illinois.edu

Office: 555B Morrill Hall

Mail to: Dept. of Cell & Developmental Biology
University of Illinois
B107 CLSL
601 S. Goodwin Avenue
Urbana, IL 61801
Lab Page

Research Assistant Professor of Cell and Developmental Biology

Research Topics

Cell-Cell Interactions, Cell-Matrix Interactions, Cytoskeleton

Disease Research Interests

Kidney Diseases

Education

B.A., University of California, Berkeley (Physiology)
Ph.D., University of California, San Francisco (Physiology)
Postdoc, Harvard Medical School, Harvard University

Teaching

Director of Renal Curriculum, Carle Illinois College of Medicine

Research

Focal and segmental glomerulosclerosis (FSGS) is a common cause of nephrotic syndrome, which accounts for up to 20% of cases in children and 40% of cases in adult. FSGS is characterized by proteinuria with high incidence of development to end-stage renal failure. Injury to or inherent within the kidney glomerular podocyte constitutes the critical event leading to FSGS. There is no specific treatment for FSGS due to the complexity of its etiology. Short of transplantation, preventing further injury to podocytes and preserving the slit diaphragm permeability barrier is key to decreasing the rate of disease progression. FSGS-associated proteinuria is primarily handled by controlling blood pressure and the administration of immunosuppressive agents. However, the potential cumulative toxicity of the various agents used for managing the disease can be as bad or worse than the disease, making FSGS one of the most difficult renal diseases to manage.

The mechanism leading to proteinuria and gross cellular damage in FSGS is not understood. Genetic linkage studies have identified several slit diaphragm proteins in the development of FSGS, including actin-regulators and cell-cell adhesion molecules. Transgenic knockout mouse models further support the roles of actin regulators and cell-cell adhesion proteins in the pathogenesis of proteinuria and FSGS. In addition, drugs that retard the progression or recurrence of FSGS can stabilize the actin cytoskeleton, suggesting that disrupting actin dynamics could be a convergent pathway to the development of FSGS.

The actin cytoskeleton participates in cell-cell adhesion and maintenance of the slit diaphragm filtration barrier in many fundamental ways. Actin organizes plasma membrane domains by clustering membrane adhesion molecules. In addition, it provides anchorage of cell-cell adhesion molecules to the underlying cytoplasmic actin network. Moreover, actin participates in mechanotransduction at sites of cell-cell adhesion and in the cytoplasm to allow adaptation to changes in glomerular pressure during health and disease. Ultimately, the actin cytoskeleton determines the validity of the glomerular filtration barrier provided by the slit diaphragm.

Given the complexity of the slit diaphragm, dissecting the structure-function relationships of its molecular components is essential to revealing the mechanism behind development of proteinuria and FSGS. The slit diaphragm is a modified adherens junction, which can be divided into three functional modules (Fig. 1a): a membrane adhesion complex (MAC) formed by transmembrane cell-cell adhesion molecules. MAC is attached to the actin cytoskeleton (Fig. 1b) via a cytoplasmic receptor complex (CRC) and a junction-actin regulatory complex (JARC). FSGS1/α-actinin-4 is recruited to the CRC to support actin assembly through a nucleation mechanism that requires the arp2/3 nucleation complex (Arp). The exact molecular nature of these modules is unclear and is the focus of our current research.

Figure 1. The slit diaphragm/adherens junction is divided into three functional modules: membrane adhesion complex (MAC), cytoplasmic receptor complex (CRC), and the junction-actin regulatory complex (JARC). (a) Addition of actin monomers to the membrane results in actin assembly promoted by the arp2/3 nucleation promoter complex (Arp). (b) Electron micrograph showing actin filaments (orange arrow) assembled on purified membrane extracted with CHAPS detergent.

Awards

Research Career Award, NIDDK, NIH

Representative Publications

Timothy Morris, Eva Sue, Caleb Geniesse, William M Brieher, Vivian W Tang (2021) Synaptopodin is required for stress fiber and contractomere assembly at the epithelial junction. bioRxiv pre-print Article

Vivian W. Tang (2020) Collagen, stiffness, and adhesion: the evolutionary basis of vertebrate mechanobiology. Molecular Biology of the Cell Perspective

Vivian W. Tang, Ambika V. Nadkarni, and William M. Brieher (2020). Catastrophic actin filament bursting by cofilin, Aip1, and coronin. Journal of Biological Chemistry Abstract

John X. H. Li, Vivian W. Tang, and William M. Brieher (2019). Actin protrusions push at apical junctions to maintain E-cadherin adhesion. Proceedings of the National Acadamy of Science Abstract Access the recommendation on F1000Prime

Nivetha Kannan and Vivian W. Tang (2018) Myosin-1c promotes E-cadherin tension and force-dependent recruitment of α-actinin to the epithelial cell junction. Highlighted in "May the FORCE be with you" J. Cell. Sci. Abstract Access the recommendation on F1000Prime

Vivian W. Tang (2018) Cell–cell adhesion interface: orthogonal and parallel forces from contraction, protrusion, and retraction. F1000Prime Perspective

Vivian W. Tang (2017) Cell-cell adhesion interface: rise of the lateral membrane. F1000Prime Perspective Access the recommendation on F1000Prime

Nivetha Kannan and Vivian W. Tang (2015) Synaptopodin couples epithelial contractility to α-actinin-4–dependent junction maturation. J. Cell Biol. 211:407-434. Abstract

Vivian W. Tang and William M. Brieher. (2013) Capping actin barbed-ends by FSGS3/CD2AP stabilizes actin at the adherens junction to strengthen epithelial cohesion and protect permeability barrier. J. Cell Biol. 203:815-833. Abstract

Vivian W. Tang and Willaim M. Brieher. (2012) Alpha-actinin-4/FSGS1 is required for arp2/3-dependent actin assembly at the adherens junction. J. Cell Biol. 196:115-130. Abstract Access the recommendation on F1000Prime

Vivian W. Tang (2006) Proteomics and bioinformatic analysis of tight junction reveals an unexpected cluster of synaptic proteins. Biology Direct 1:37. Abstract Access the recommendation on F1000Prime