Jonathan Allen Cohn, MD

Professor of Medicine
Associate Professor of Cell Biology
Professor in Pediatrics
Campus mail DUMC Box 3256, Durham, NC 27710
Phone (919) 684-6879
Email address jonathan.cohn@duke.edu

In many epithelial tissues, the protein mainly responsible for controlling transepithelial fluid movement is the the cystic fibrosis transmembrane conductance regulator (CFTR). CFTR was originally identified as the protein product of the gene causing cystic fibrosis (CF). CFTR functions as a chloride channel regulated by protein kinase A (PKA). This laboratory is studying the role and regulation of CFTR. One project focuses on how PKA acts on CFTR. In this project, recombinant peptide models are being used to model the cytoplasmic domains of CFTR responsible for activating the protein's chloride's chloride channel function. Site-directed mutagenesis is being used to produce modified peptides to study how different individual serine phosphoryation contribute to CFTR regulation. A second project concerns DF508, the most common mutation among patients with CF. This mutation affects CFTR function by preventing normal folding and intracellular trafficking of the newly synthesized mutant protein. This project is examining the mislocalization of DF508-CFTR in tissues and cell lines with the long term goal of developing strategies to prevent the mutant protein from mislocalizing. A third project concerns the role of CFTR in chronic pancreatitic diseases. Emerging data about the role of CFTR during normal pancreatic secretion suggests that dysfunction of this protein may lead to pancreatic diseases such as chronic pancreatitis and pancreatic cancer. Patients with these chronic pancreatic diseases are being tested for CFTR mutations and for evidence of defective CFTR function.

Education and Training

  • Fellow in Gastroenterology, Medicine, Yale University, 1981 - 1984
  • Medical Resident, Medicine, University of California San Francisco, School of Medicine, 1980 - 1981
  • Medical Resident, Medicine, University of Alabama Birmingham, 1978 - 1980
  • M.D., Cornell University, 1978

Publications

Engelhardt, J. F., M. Zepeda, J. A. Cohn, J. R. Yankaskas, and J. M. Wilson. “Expression of the cystic fibrosis gene in adult human lung.” J Clin Invest 93, no. 2 (February 1994): 737–49. https://doi.org/10.1172/JCI117028.

PMID
7509347
Full Text

Ernst, S. A., K. M. Crawford, M. A. Post, and J. A. Cohn. “Salt stress increases abundance and glycosylation of CFTR localized at apical surfaces of salt gland secretory cells.” American Journal of Physiology  Cell Physiology 267, no. 4 37-4 (January 1, 1994).

Scholars@Duke

Cohn, J. A., T. V. Strong, M. R. Picciotto, A. C. Nairn, F. S. Collins, and J. G. Fitz. “Localization of the cystic fibrosis transmembrane conductance regulator in human bile duct epithelial cells.” Gastroenterology 105, no. 6 (December 1993): 1857–64. https://doi.org/10.1016/0016-5085(93)91085-v.

PMID
7504645
Full Text

Yang, Y., S. Janich, J. A. Cohn, and J. M. Wilson. “The common variant of cystic fibrosis transmembrane conductance regulator is recognized by hsp70 and degraded in a pre-Golgi nonlysosomal compartment.” Proc Natl Acad Sci U S A 90, no. 20 (October 15, 1993): 9480–84. https://doi.org/10.1073/pnas.90.20.9480.

PMID
7692448
Full Text

Cohn, J. A., J. Kole, and J. R. Yankaskas. “Protein phosphorylation responses in normal and cystic fibrosis airway epithelial cell lines.” Am J Respir Cell Mol Biol 9, no. 4 (October 1993): 401–4. https://doi.org/10.1165/ajrcmb/9.4.401.

PMID
8398178
Full Text

Yang, Y., D. C. Devor, J. F. Engelhardt, S. A. Ernst, T. V. Strong, F. S. Collins, J. A. Cohn, R. A. Frizzell, and J. M. Wilson. “Molecular basis of defective anion transport in L cells expressing recombinant forms of CFTR.” Hum Mol Genet 2, no. 8 (August 1993): 1253–61. https://doi.org/10.1093/hmg/2.8.1253.

PMID
7691345
Full Text

Basavappa, S., J. Middleton, A. W. Mangel, J. M. McGill, J. A. Cohn, and J. G. Fitz. “Cl- and K+ transport in human biliary cell lines.” Gastroenterology 104, no. 6 (June 1993): 1796–1805. https://doi.org/10.1016/0016-5085(93)90661-u.

PMID
7684717
Full Text

Yang, Y., S. E. Raper, J. A. Cohn, J. F. Engelhardt, and J. M. Wilson. “An approach for treating the hepatobiliary disease of cystic fibrosis by somatic gene transfer.” Proc Natl Acad Sci U S A 90, no. 10 (May 15, 1993): 4601–5. https://doi.org/10.1073/pnas.90.10.4601.

PMID
7685107
Full Text

VAJANAPHANICH, M., U. KACHINTORN, K. E. BARRETT, J. A. COHN, K. DHARMSATHAPHORN, and A. TRAYNORKAPLAN. “PHOSPHATIDIC-ACID MODULATES CL(-) SECRETION IN T84-CELLS - VARYING EFFECTS DEPENDING ON MODE OF STIMULATION.” American Journal of Physiology 264, no. 5 (May 1, 1993): C1210–18.

Scholars@Duke

Vajanaphanich, M., U. Kachintorn, K. E. Barrett, J. A. Cohn, K. Dharmsathaphorn, and A. Traynor-Kaplan. “Phosphatidic acid modulates Cl- secretion in T84 cells: varying effects depending on mode of stimulation.” Am J Physiol 264, no. 5 Pt 1 (May 1993): C1210–18. https://doi.org/10.1152/ajpcell.1993.264.5.C1210.

PMID
8388632
Full Text

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