Cystic fibrosis is a highly variable disorder of fluid and electrolyte transport that primarily affects the lung, pancreas, intestine, male reproductive tract and the sweat gland. Positional cloning identified CF Transmembrane conductance Regulator (CFTR) as the gene responsible for CF. It has been demonstrated that normal function of CFTR requires 1) efficient folding in the endoplasmic reticulum, 2) targeting to apical membranes in epithelial cells, 3) activation by b-adrenergic cAMP-dependent pathways, 4) generation of endogenous CI- currents and 5) regulation of separate sodium and chloride channels (and possibly other channels and transporters). The vexing question has been which process, or combination of processes, when altered by mutation in CFTR correlates with the severity of disease? We and others have shown that mutations found in patients can affect each of these processes, and that alteration in the maturation (#1) and chloride transport processes (#4) of CFTR partially correlate with disease severity. During the prior phase of this grant, we demonstrated that alteration in the regulatory function of CFTR (#5) correlates with disease severity, but only for some mutations. Thus, the mechanism by which certain mutations cause disease is unknown. The overall goal of this grant is to increase our understanding of CF pathophysiology by investigating the contribution of localization defects (#2) and altered cAMP-activation (#3) to the development of the CF phenotype. This will be achieved by pursuit of the following aims: 1) To identify proteins interacting with the C-terminus that participate in CFTR localization to apical membranes of polarized epithelial cells. 2) To determine whether mutations in regions other than the C-terminus affect CFTR localization and correlate with disease severity. 3) To determine whether defects in components of the cAMP-activation pathway alters CFTR function and creates a CF phenotype.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Method to Extend Research in Time (MERIT) Award (R37)
Project #
5R37DK044003-21
Application #
8060474
Study Section
Special Emphasis Panel (NSS)
Program Officer
Mckeon, Catherine T
Project Start
1991-05-01
Project End
2013-04-30
Budget Start
2011-05-01
Budget End
2012-04-30
Support Year
21
Fiscal Year
2011
Total Cost
$393,479
Indirect Cost
Name
Johns Hopkins University
Department
Pediatrics
Type
Schools of Medicine
DUNS #
001910777
City
Baltimore
State
MD
Country
United States
Zip Code
21218
Sharma, Neeraj; Sosnay, Patrick R; Ramalho, Anabela S et al. (2014) Experimental assessment of splicing variants using expression minigenes and comparison with in silico predictions. Hum Mutat 35:1249-59
Sosnay, Patrick R; Siklosi, Karen R; Van Goor, Fredrick et al. (2013) Defining the disease liability of variants in the cystic fibrosis transmembrane conductance regulator gene. Nat Genet 45:1160-7
Ferec, Claude; Cutting, Garry R (2012) Assessing the Disease-Liability of Mutations in CFTR. Cold Spring Harb Perspect Med 2:a009480
Henderson, Lindsay B; Doshi, Vishal K; Blackman, Scott M et al. (2012) Variation in MSRA modifies risk of neonatal intestinal obstruction in cystic fibrosis. PLoS Genet 8:e1002580
Romi, Hila; Cohen, Idan; Landau, Daniella et al. (2012) Meconium ileus caused by mutations in GUCY2C, encoding the CFTR-activating guanylate cyclase 2C. Am J Hum Genet 90:893-9
Sosnay, Patrick R; Castellani, Carlo; Corey, Mary et al. (2011) Evaluation of the disease liability of CFTR variants. Methods Mol Biol 742:355-72
Sheridan, Molly B; Hefferon, Timothy W; Wang, Nulang et al. (2011) CFTR transcription defects in pancreatic sufficient cystic fibrosis patients with only one mutation in the coding region of CFTR. J Med Genet 48:235-41
Lassance-Soares, Roberta M; Cheng, Jie; Krasnov, Kristina et al. (2010) The hypertonic environment differentially regulates wild-type CFTR and TNR-CFTR chloride channels. Cell Physiol Biochem 26:577-86
Quemener, Sylvia; Chen, Jian-Min; Chuzhanova, Nadia et al. (2010) Complete ascertainment of intragenic copy number mutations (CNMs) in the CFTR gene and its implications for CNM formation at other autosomal loci. Hum Mutat 31:421-8
Kohonen-Corish, Maija R J; Al-Aama, Jumana Y; Auerbach, Arleen D et al. (2010) How to catch all those mutations--the report of the third Human Variome Project Meeting, UNESCO Paris, May 2010. Hum Mutat 31:1374-81

Showing the most recent 10 out of 40 publications