Associate Professor, Biology/Neuroscience Dominican University River Forest, IL
Transcriptional Correlates of Savings Memory for Long-Term Sensitization in Aplysia californica
Most long-term memories fade, becoming progressively less likely to be recalled. Although psychologists have studied forgetting for over a century, the neurobiology of memory loss remains shrouded in mystery. I will review research from our own lab exploring the neurobiology of memory encoding and loss in the marine mollusk Aplysia calinfornica.
March 7th, 2018 1:00 - 2:00pm School of Medicine, Room 132A
Professor, Dept. Physiology & Pharmacology, Canada Research Chair (Tier 1) in Intestinal Immunophysiology University of Calgary
Mitochondria regulate epithelial-bacteria interactions: implications for the gut barrier
The microbiota of the gut is an important determinant of health and well-being, where loss of diversity is described in inflammatory bowel disease (IBD): bacteria can be found within the gut epithelium of patients with IBD, and their epithelial barrier function is often decreased. Deranged epithelial mitochondria can also occur in enterocytes from patients with IBD. I will present one mechanism by which targeted disruption of mitochondrial function with the uncoupling agent, dinitrophenol, results in increased internalization of non-invasive E. coli by metabolically-stressed epithelial. Considering connectivity with the transporting epithelial cell, mitochondria are functionally coupled to the ER, and ER stress (an unfolded protein response) has been described in IBD. I hypothesized that the combination of ER and mitochondrial stress would significantly disrupt epithelial barrier function. Contrary to my expectation, induction of ER-stress protects against decreased barrier function caused by disruption of mitochondrial function, as assessed by viable intracellular bacteria and E. coli transcytosis. ER-stress did not prevent DNP-driven uptake of bacteria; rather, specific mobilization of the ATF6-arm of ER stress and then DAPK-1 resulted in enhanced autophagic killing of bacteria. Finally, epithelia infected with the putative pathobiont, adherent-invasive E. coli (AIEC, strain LF82) demonstrate significant fragmentation of their mitochondrial network. Collectively, these studies are revealing the importance of mitochondrial function in regulating the host-microbe relationship, specifically enteric epithelial-commensal bacteria interaction, which may identify novel ways to maintain homeostasis and promote digestive health.
March 14th, 2018 1:00 - 2:00pm School of Medicine, Room 132A