Department of Physiology

Norman Rosenblum MD
Reproduction and Development Platform
Contact Info
T: (416) 813-5667
F: (416) 813-5252
Peter Gilgan Centre for Research and Learning, The Hospital for Sick Children, 686 Bay Street, Rm 16-9706
Toronto, ON, M5G 0A4
Primary: Paediatrics.
Research Interests
Cellular and molecular mechanisms which control formation of the normal and malformed mammalian kidney and cerebellum. Growth factor signaling during tissue morphogenesis with particular focus on Hedgehog signaling.

Staff Nephrologist and Senior Scientist, The Hospital for Sick Children
Professor of Paediatrics, Physiology, and Laboratory Medicine and Pathobiology,
Associate Dean, Physician Scientist Training, University of Toronto


Research Synopsis

Keywords: Renal development , branching morphogenesis, bone morphogenetic proteins, renal dysplasia, sonic hedgehog, beta-catenin, cerebellum.

Detailed Description: The kidney is a paradigm for understanding the molecular control of embryonic mesenchymal-epithelial tissue interactions and how growth factor-dependent signaling controls mammalian organogenesis. Maldevelopment of the embryonic kidney and urinary tract is the major cause of childhood renal failure. Despite the importance of kidney and urinary tract development to health and disease, the underlying molecular mechanisms are largely unknown.

The kidney arises via reciprocal inductive interactions between a mesenchymal tissue, the metanephric blastema, and an epithelial tube, the ureteric bud. The blastema is induced to form nephrons, which consist of the glomerulus and the tubules proximal to the collecting ducts. The ureteric bud is induced to grow and branch, a process termed branching morphogenesis, and give rise to all the components of the collecting system including the collecting ducts, calyces, pelvis and ureter. Formation of a critical number of nephrons is required for normal kidney function and is dependent on both metanephric development and branching morphogenesis.

The major focus of research in my lab is to define mechanisms by which secreted growth factors and their cognate receptors control branching morphogenesis, formation of a contractile ureter, and generation of nephrons. We study these mechanisms using primary kidney cell cultures, tissue explants, transgenic mice and 'knock-out' mice.

We are investigating the actions of three major signaling pathways activated by Bone Morphogenetic Proteins (BMP), Sonic Hedgehog (SHH) and WNTs, respectively, primarily during kidney development and also during cerebellar morphogenesis. Our work in the embryonic kidney demonstrates that WNTs, HHs and BMPs play multifunctional roles to control morphogenesis of metanephric mesenchyme- and ureteric-derived tissues. In the cerebellum, signaling via HH effectors controls mid-hindbrain patterning, cell differentiation and tissue patterning.  We are futher defining these actions at the level of cell-cell interactions, signaling mechanisms and transcription of genes that are essential during kidney and cerebellar development.


Cell and tissue culture: Neurons

Procedures: Gene expression analysis, immunohistochemistry, immunocytochemistry, microarrays, qRT-PCR, RT-PCR, signal transduction characterization, siRNA, western blot


Analytical balances, benchtop centrifuge, blotting apparatus, culture hood, culture incubators, deconvolution fluorescence microscope, dissecting microscope, fluorescence microscope, gel apparatus, low and ultralow freezers, microwave oven, ProBlot hybridization oven, water baths


Tayyaba Jiwani
Chris Rowan
Sepideh Sheybani Deloui


Within the Department of Physiology:
Freda Miller

Outside the Department of Physiology:
Chi-chung Hui, Molecular Genetics, University of Toronto
Mark Henkelman, Department of Medical Biophysics, University of Toronto
Branden Wainwright, Department of Molecular Bioscience, University of Queensland
Steve Potter, Department of Developmental Biology, University of Cincinnati

Committee member/officer of national/international scientific organizations
Canadian Society for Clinical Investigation
EUREKA Institute for Translational Medicine
Royal College of Physicians and Surgeons of Canada Clinical Investigator Program
Pediatric Scientist Development Program
American Pediatric Society
Canadian Society of Nephrology

Agency: CIHR
Committee: Hematology, Digestive Disease, Kidney Operating Grants Committee

Agency: Alberta Innovates
Committee: Health Professional Fellowship Committee

Publications and Awards

View PubMed search of this faculty member's recent publications.

Recent Publications