Varsha Singh, PhD

Co-Director, Ross Research Confocal Microscopy Core Facility

Dr. Singh's Lab seeks to understand mechanisms that regulate intestinal epithelial cell function during homeostasis and pathophysiological conditions. We are working to understand the trafficking and molecular regulation of membrane proteins in diarrheal diseases, epithelial stem cell differentiation during homeostasis, and chronic inflammatory conditions including IBD, and T1D. To investigate these mechanisms at the tissue, cell, and molecular levels, we apply in vivo (mouse transgenics), ex vivo (2D, 3D organotypic culture), imaging (live, confocal/2photon), and RNA sequencing technologies. The broader goal of our research is to exploit signaling pathways to suggest targeted approaches for new treatment strategies for GI diseases.

720 Rutland Avenue
Johns Hopkins School of Medicine
Baltimore, MD 21205

cellular physiology, Intestinal ion transport, membrane trafficking, stem cell biology, epithelial differentiation

• The Singh Lab does basic and translational research on intestinal ion transport, cellular physiology, and membrane trafficking in diabetic disorders.

1. Donowitz M, Singh V. (2026) INSL5 as a newly recognised potential contributor to diarrhoea pathogenesis: more questions than answers. Gut. 2026 Jan 8;75(2):428-429. doi: 10.1136/gutjnl-2025-336674.
2. Bharadiya V, Rong Y, Zhang Z, Lin R, Guerrerio AL, Tse CM, Donowitz M, Singh V. (2024) Type 1 diabetes human enteroid studies reveal major changes in the intestinal epithelial compartment. Sci Rep. 2024 May 24;14(1):11911. doi: 10.1038/s41598-024-62282-x.
3. Donowitz M, Sarker R, Lin R, McNamara G, Tse CM, Singh V. (2022) Identification of Intestinal NaCl Absorptive-Anion Secretory Cells: Potential Functional Significance. Front Physiol. 2022 Jul 19;13:892112. doi: 10.3389/fphys.2022.892112. eCollection 2022.
4. Tse CM, Yin J, Singh V, Sarker R, Lin R, Verkman AS, Turner JR, Donowitz M. (2019) cAMP Stimulates SLC26A3 Activity in Human Colon by a CFTR-Dependent Mechanism That Does Not Require CFTR Activity. Cell Mol Gastroenterol Hepatol. 2019;7(3):641-653. doi: 10.1016/j.jcmgh.2019.01.002. Epub 2019 Jan 17.
5. Singh V, Yang J, Cha B, Chen TE, Sarker R, Yin J, Avula LR, Tse M, Donowitz M. (2015) Sorting Nexin 27 regulates basal and stimulated Brush Border Trafficking of NHE3 (Mol Biol Cell. 2015 Jun 1;26(11):2030-43. (F1000 recommendation)