Chandrasekar Lab

Graduate Student Mentor

COBRE Project Leader

Primary Research Focus

Kidneys play a crucial role in maintenance of pH, water, and electrolyte balance in our body. The renal epithelial cells that perform the ion and water reabsorption are diverse in nature. Chandrasekar lab is interested in understanding the role of the actin cytoskeleton and associated myosin motor proteins in regulation of renal epithelial transport pathways and transport related kidney disease. We use a multifaceted approach involving conditional knockout mouse models, cell biological, biochemical methods including advanced microscopy techniques. The lab is also involved in development and application of novel tools and techniques to study membrane remodeling, organelle structure and function in vitro in cell culture and in vivo in mouse and human kidneys.

Primary Research Group

Enabling Technologies

Secondary Research Groups

Pediatrics and Rare Diseases

(605) 312-6071

(605) 312-6412

Email Dr. Chandrasekar

About the Chandrasekar Lab

About Indra Chandrasekar, Associate Scientist

Indra obtained her Master’s degree from Birla Institute of Technology and Science, Pilani, India. Her passion for Cell Biology took her to cytoskeletal research pioneer, Dr. Brigitte M. Jockusch’s Lab in Germany, where she received training in basic cell biology concepts and techniques. After receiving her Ph.D. (Dr.rer.nat) degree from Technical University of Braunschweig in Germany, she moved to the US. Indra performed a short postdoctoral fellowship in the laboratory of renowned actin biologist, Dr.John Cooper at Washington University School of Medicine in St. Louis, to continue her training in cytoskeletal research. Consequently, she joined the lab of Dr. Paul Bridgman, an expert cellular neurobiologist and EM specialist at Washington University, where she received training in neuronal cytoskeleton, mouse models and advanced microscopy techniques. As an independent investigator, Indra’s scientific interest has been in two broad areas of research – 1) understanding cellular transport pathways from an organismal and physiological perspective and 2) developing novel tools and techniques to understand the mechanism(s) involved in specialized cellular transport and other biophysical characteristics of cells. More specifically, the Chandrasekar lab is interested in understanding the role of actin cytoskeleton and associated motor proteins in renal epithelial cargo transport in the kidney and transport related kidney disease.

Academic Affiliations and Training

Academic Affiliations:

Associate Professor, Department of Pediatrics, University of South Dakota
Associate Professor, Department of Chemistry and Biochemistry, South Dakota State University
Sanford Histology and Imaging core director (2015-present)
Staff Scientist, Department of Anatomy & Neurobiology, Washington University School of Medicine (2012 - 2013)

Professional Memberships:

American Society for Cell Biology
American Society of Nephrology
American Physiological Society

Highlighted Publications

Otterpohl KL, Busselman BW, Ratnayake I, Hart RG, Hart KR, Evans CM, Phillips CL, Beach JR, Ahrenkiel P, Molitoris BA, Surendran K, Chandrasekar I. Conditional Myh9 and Myh10 inactivation in adult mouse renal epithelium results in progressive kidney disease. JCI Insight. 2020 Nov 5;5(21). doi: 10.1172/jci.insight.138530. PubMed PMID: 33001861; PubMed Central PMCID: PMC7710296.

Otterpohl KL, Hart RG, Evans C, Surendran K, Chandrasekar I. Nonmuscle myosin 2 proteins encoded by Myh9, Myh10, and Myh14 are uniquely distributed in the tubular segments of murine kidney. Physiol Rep. 2017 Dec;5(23). doi: 10.14814/phy2.13513. PubMed PMID: 29208685; PubMed Central PMCID: PMC5727274.

Chandrasekar I, Goeckeler ZM, Turney SG, Wang P, Wysolmerski RB, Adelstein RS, Bridgman PC. Nonmuscle myosin II is a critical regulator of clathrin-mediated endocytosis. Traffic. 2014 Apr;15(4):418-32. doi: 10.1111/tra.12152. Epub 2014 Feb 12. PubMed PMID: 24443954; PubMed Central PMCID: PMC3975594

Otterpohl KL, Busselman BW, Zimmerman JL, Mukherjee M, Evans C, Graber K, Thakkar VP, Johnston JG, Ilyas A, Gumz ML, Eaton DC, Sands JM, Surendran K, Chandrasekar I. Thick Ascending Limb Specific Inactivation of Myh9 and Myh10 Myosin Motors Results in Progressive Kidney Disease and Drives Sex-specific Cellular Adaptation in the Distal Nephron and Collecting Duct. Function (Oxf). 2025 Feb 12;6(1):zqae048. doi: 10.1093/function/zqae048. PMID: 39500539.
Highlighted in “Stuck in Traffic-Myosin Motors Ease Gridlock in the Loop. Curry JN, McCormick JA. Function (Oxf). 2025 Feb 12;6(1):zqaf008. doi: 10.1093/function/zqaf008.PMID: 39986266.

Hart RG, Kota D, Li F, Zhang M, Ramallo D, Price AJ, Otterpohl KL, Smith SJ, Dunn AR, Huising MO, Liu J, Chandrasekar I. Myosin II tension sensors visualize force generation within the actin cytoskeleton in living cells. J Cell Sci. 2024 Oct 15;137(20):jcs262281. doi: 10.1242/jcs.262281. Epub 2024 Oct 30. PMID: 39369303.

Busselman BW, Ratnayake I, Terasaki MR, Thakkar VP, Ilyas A, Otterpohl KL, Zimmerman JL, Chandrasekar I. Actin cytoskeleton and associated myosin motors within the renal epithelium. Am J Physiol Renal Physiol. 2024 Oct 1;327(4):F553-F565. doi: 10.1152/ajprenal.00078.2024. PMID: 39052845. Review.

Read All Publications

Mentees

Ryan Hart, Research Associate, Graduate Student BMCDB program, UC Davis

Kevin Shan, Promise Scholar, Medical Student, University of Rochester

Dr. Karla Otterpohl (2015 – 2024) – Postdoc/Staff Scientist. Current Position: Regulatory Affairs, Aviva Therapeutics.

Ms. Jenna Zimmerman (2021 – 2025) – Research Specialist. Current Position: MPH/MBA dual degree student, UNMC.

Lab News

Dr. Indra Chandrasekar and her team attended the American Physiological Society Summit in Long Beach, California. The summit united leading experts in physiology to discuss the latest advances and challenges.

The team participated in various sessions:

PhD student Brook Busselman presented his findings on "Automated serial section electron microscopy and 3D reconstruction reveals role for nonmuscle myosin II in organelle structure and cargo transport regulation within the murine kidney thick ascending limb" in the Epithelial Transport Session.

Dr. Karla Otterpohl, a staff scientist, shared insights on "Aberrant adaptation of the inner medullary collecting ducts results in sodium retention and hypernatremia in a thick ascending limb specific Myh9 and Myh10 conditional knockout mouse model" in the Channels, Transporters and Pumps in Health and Disease Session." Dr. Kamesh Surendran was a co-author on the abstract.

Research specialist Jenna Zimmerman presented her findings on "Nonmuscle myosin II proteins, Myh9 and Myh10, interacts with unconventional myosin Myo18A in immortalized mouse thick ascending limb epithelial cells" in the Protein Trafficking and Cell Polarity Session.

Lab Projects

Generation of Novel Biosensor to Measure Intracellular Tension

We have successfully generated a FRET-based biosensor of NMII that enables us to measure force generated along the actin filaments in live cells. We collaborate with Dr. Jing Liu, an expert biophysicist at Indiana University for this work. In addition to the biological questions, we are addressing using this biosensor; this novel tool can be of use to scientists from various fields such as cancer biology, bioengineering, material science etc.

Role of Myosin motor proteins in regulating cargo transport

Our previous work demonstrated that the loss of some proteins in mouse renal epithelium resulted in abnormal transport of thick ascending limb (TAL) cargo proteins, sodium, potassium, and a chloride cotransporter which led to progressive kidney disease. We utilize this mouse model and a new TAL-specific mouse model to further investigate the mechanisms by which these molecular motor proteins regulate cargo transport and influence ion reabsorption in the kidneys.

Novel immortalized thick ascending limb epithelial cell culture system to study cellular transport in vitro.

We generated an immortalized thick ascending limb (imTAL) cell line from the adult kidneys of mice that had been genetically modified with the immortomouse transgene. We perform biological and biochemical testing to assess the anterograde transport of cargo proteins and perturbations in the organelle transport pathways.

Conditional Myh9 and Myh10 inactivation in adult mouse renal epithelium results in progressive kidney disease

In 2020, our lab published a paper in the JCI Insight journal that highlights the critical role of actin-associated myosin motor nonmuscle myosin II (Myh9 and Myh10) in regulating specialized renal epithelial cargo transport machinery and kidney function. Our work established Myh9 and Myh10 playing a causal role in renal tubular disease, which is of significant interest since mutations in the MYH9 gene in humans result in kidney disease in at least one-third of patients.

3D reconstruction of organelles in the mouse kidney

We hypothesize that some proteins may regulate endoplasmic reticulum transport. To address this, our goal is to develop and standardize techniques and tools to visualize endoplasmic reticulum structure and dynamics in adult mouse renal epithelial cells using new 3D reconstruction technology.

Generation of Novel Biosensor to Measure Intracellular Tension

Role of Myosin motor proteins in regulating cargo transport

Novel immortalized thick ascending limb epithelial cell culture system to study cellular transport in vitro.

Conditional Myh9 and Myh10 inactivation in adult mouse renal epithelium results in progressive kidney disease

3D reconstruction of organelles in the mouse kidney

Generation of Novel Biosensor to Measure Intracellular Tension

Meet the Chandrasekar Lab Team

Arooba Ilyas

PhD Student

Arooba Ilyas earned her Bachelors of Science Degree in Biology from the University of Arkansas at Little Rock, and her Masters of Science in Biomedical Sciences from the New York Institute of Technology's College of Osteopathic Medicine (NYITCOM). She recently joined the Chandrasekar Lab (May 2024) where she will be investigating progressive kidney disease of tubular origins. Arooba Ilyas has a background in teaching as she has been a biology, chemistry, and MCAT tutor for several years.

Karla Otterpohl, PhD

Staff Scientist

Karla is involved in developing and characterizing the various genetic knockout mouse models we use in the lab. She also performs advanced imaging techniques like TIRFM and live cell confocal imaging to interrogate the role of NMII isoforms in cellular transport pathways. Karla is an expert mouse geneticist with extensive training in genetic mouse models and molecular biology techniques. In the Chandrasekar Lab she has worked on expanding her skill set to advanced microscopy techniques and cytoskeletal research. She earned a PhD from the University of Nebraska Medical Center in 2015.

Brook W. Busselman

Postdoctoral Fellow

Brook joined the Chandrasekar lab in May 2019. His responsibility is to explore the molecular link between three human kidney disease-related genes: uromodulin (UMOD), Sodium potassium chloride cotransporter (NKCC2) and Nonmuscle Myosin IIA (MYH9). He works with conditional genetic knockout mouse models, novel mouse thick ascending limb cells generated in the lab to address the questions. Brook completed his undergraduate studies in medical biology at University of South Dakota. He has several years of work experience in pre-hospital emergency medicine and has gained other lab experience. Brook received his PhD from University of South Dakota in May 2024. His thesis project demonstrated the critical role for Myosin 2 motors in the thick ascending limb (TAL) cargo transport in the kidney. In collaboration with Dr. Mark Terasaki at UCONN, his project utilized automated tape collecting ultramicrotome – scanning electron microscopy (ATUM-SEM) and 3D reconstruction methods to visualize organelle architecture (ER, Mitochondria, Plasma membrane) within the TAL cells. Brook is continuing his research on organelle architecture using innovative immunostaining methods.

Jenna Zimmerman

Research Specialist

Jenna joined the Chandrasekar lab in June 2021. She is using biochemical techniques to investigate the role of NMII isoforms in the kidney. She earned a bachelor’s degree in biology from the University of Wisconsin-La Crosse in 2021.

Vedant Thakkar

Research Specialist

Vedant Thakkar is a research specialist in the Chandrasekar Lab at Sanford Research. He recently graduated from Augustana University with a Bachelor of Arts in Biology with Honors. Within his current role, Vedant is involved in research into the role of actin cytoskeleton and myosin motor proteins in the regulation of ion transport in mouse renal epithelium. He standardizes techniques for immunostaining of vibratome kidney sections and combining them with super-resolution microscopy. Also, he assists with mouse genotyping and other lab management duties.