Varsha Singh, Ph.D.

Headshot of Varsha Singh
  • Assistant Professor of Medicine

Research Interests

Intestinal ion transport; cellular physiology; membrane trafficking more


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. more


  • Assistant Professor of Medicine

Departments / Divisions



  • Ph.D.; Banaras Hindu University (India) (2009)

Research & Publications

Selected Publications

View all on PubMed

Cha B, Yang J, Singh V, Zachos NC, Sarker RI, Chen TE, Chakraborty M, Tse CM, Donowitz M.PDZ Domain Dependent Regulation of NHE3 Occurs by Both Internal Class II and C-terminal Class I PDZ Binding Motifs. J Biol Chem. 2017 Mar 10.[Epub ahead of print]

Jianbo Yang; Rafiquel Sarker; Varsha Singh; Prateeti Sarker; Jianyi Yin; Tian-e Chen; Raghothama Chaerkady; Xuhang Li; Chung Ming Tse; Mark Donowitz The NHERF2 sequence adjacent and upstream of the ERM binding domain affects NHERF2-ezrin binding and dexamethasone stimulated NHE3 activity Biochem J. 2015 Aug 15;470(1):77-90 

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)

Tiane Chen, Hetal S. Kocinsky, Rakhilya Murtazina, Boyoung Cha, Jianbo Yang, Tse CM, Varsha Singh, Rafiquel Sarker, Robert Cole, Peter S. Aronson, Hugo deJonge and Mark Donowitz. (2014) Cyclic GMP Kinase II (cGKII) Inhibits NHE3 by Altering its Trafficking and Phosphorylating NHE3 at Three Required Sites: Identification of a Multifunctional Phosphorylation Site (J Biol Chem 290(4):1952-65.)

Yang, J., Singh, V., Chen, T. E., Sarker, R., Xiong, L., Cha, B., Jin, S., Li, X., Tse, C. M., Zachos, N. C., and Donowitz, M. (2014) NHERF2/NHERF3 Protein Heterodimerization and Macrocomplex Formation Are Required for the Inhibition of NHE3 Activity by Carbachol. J Biol Chem 289, 20039-20053

Contact for Research Inquiries

Ross 933B
720 Rutland Avenue
Johns Hopkins School of Medicine
Baltimore, MD 21205 map

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