Primary cilia are small projections present on the surface of most vertebrate cell types. Defects in these structures have been associated with a growing list of disorders including Bardet-Biedl Syndrome, Polycystic Kidney Disease, and Nephronophthisis, among others. Though several developmental signaling pathways are known to be regulated by cilia, a clear understanding of the extent of their involvement in signal transduction remains elusive. Notch signaling, in particular, may be associated with cilia and may, therefore, underlie ciliopathy phenotypes. We hypothesize that defects in primary cilia result in perturbation of Notch signaling and that this regulation results in disruption of associated developmental processes. Specifically, we hypothesize that cilia-dependent defects in Notch underlie pancreatic defects and diabetes, which are prevalent in ciliopathy patients. Using a zebrafish model and in vitro systems, we propose to test this hypothesis by two specific aims. First, we will investigate the mechanistic link between disruption of ciliary function and perturbation of Notch signaling during development. We will then investigate a role for cilia in pancreatic development and function. The proposed research builds on Dr. Zaghloul's previous training in developmental genetics and ciliary biology. She will be guided by mentors with expertise in the areas of molecular mechanisms and genetics of diabetes, pancreatic development and function, and zebrafish development. The expertise gained as a result of this Career Development Award will poise Dr. Zaghloul to launch a fully independent career investigating cililary regulation of complex phenotypes. The research studies outlined here will establish a zebrafish model of ciliary dysfunction with a specific focus on pancreatic phenotypes. The overall proposal is strengthened by: 1) a specific focus on Notch signaling and an associated phenotype that has been largely unexplored in the context of cilia, and 2) a strong team of mentors with recognized expertise investigating these phenotypes. An improved understanding of the molecular mechanisms underlying these phenotypes may suggest common links between ciliopathies and common traits and provide new insights into the treatment of these conditions.

Public Health Relevance

Pancreatic defects and diabetes are prevalent in patients with mutations in genes that make up primary cilia, tiny projections present on the surface of most cell types. The proposed studies seek to investigate how primary cilia regulate developmental processes that contribute to pancreatic development and the onset of diabetes.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Scientist Development Award - Research & Training (K01)
Project #
1K01DK092402-01
Application #
8165288
Study Section
Diabetes, Endocrinology and Metabolic Diseases B Subcommittee (DDK)
Program Officer
Hyde, James F
Project Start
2011-07-01
Project End
2014-04-30
Budget Start
2011-07-01
Budget End
2012-04-30
Support Year
1
Fiscal Year
2011
Total Cost
$113,099
Indirect Cost
Name
University of Maryland Baltimore
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
188435911
City
Baltimore
State
MD
Country
United States
Zip Code
21201
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