Administration	Basic Sciences	Clinical Sciences	Centers of Excellence
Admissions Alumni Affairs Community and Minority Health Education Computer Support Continuing Education Dean's Office Faculty & Institutional Affairs Fiscal Affairs Libraries Medical Education Research Student Affairs	Biochemistry & Molecular Biology Cell Biology & Anatomy Genetics Microbiology, Immunology & Parasitology Pharmacology Physiology	Anesthesiology Dermatology Family Medicine Internal Medicine Emergency Medicine Gastroenterology Physical Medicine & Rehabilitation Neurology Neurosurgery OB/GYN Ophthalmology Orthopaedics Otorhinolaryngology Pathology Pediatrics Psychiatry Radiology Surgery Urology	Alcohol and Drug Abuse Center Cardiovascular Center Center on Healthy Aging Center for Molecular and Human Genetics Epilepsy Center Eye Center Ernest N. Morial Asthma, Allergy, and Respiratory Disease Center Gene Therapy Program Low Vision Center Neurosciences Center The Research Institute For Children Stanley S. Scott Cancer Center

Cholera toxin and the heat-labile enterotoxin have differential effects on intestinal endocrine cells.

Principal Investigator: Bonny L. Dickinson, Ph.D.

Abstract

Cholera toxin (CT) and the heat-labile enterotoxin (LT) are AB5 bacterail toxins that cause secretory diarrhea. Although the toxins are structurally related, there are important differences that make them unique. CT exclusively binds GM1 ganglioside, present on the surface of all nucleated cells, while LT has a much broader binding specificity and binds receptors containing an N-terminal galactose moiety. In addition, the toxins contain different endoplasmic reticulum targeting and retention signals, associate with different proteins that affects toxin intracellular trafficking, and their enzymatic activity modulates different cellular targets. We are interested in determining how these differences influence toxin interaction with and modulation of intestinal endocrine cells, specialized cells that reside within the epithelial barrier of the small and large intestines.