title: Heat stress enhances LTM formation in Lymnaea: role of HSPs and DNA methylation.
abstract: Environmentally relevant stressors alter the memory-forming process in Lymnaea following operant conditioning of aerial respiration. One such stressor is heat. Previously, we found that following a 1 h heat shock, long-term memory (LTM) formation was enhanced. We also had shown that the heat stressor activates at least two heat shock proteins (HSPs): HSP40 and HSP70. Here, we tested two hypotheses: (1) the production of HSPs is necessary for enhanced LTM formation; and (2) blocking DNA methylation prevents the heat stressor-induced enhancement of LTM formation. We show here that the enhancing effect of the heat stressor on LTM formation occurs even if snails experienced the stressor 3 days previously. We further show that a flavonoid, quercetin, which inhibits HSP activation, blocks the enhancing effect of the heat stressor on LTM formation. Finally, we show that injection of a DNA methylation blocker, 5-AZA, before snails experience the heat stressor prevents enhancement of memory formation.
authors.affiliation: Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada T2N 4N1.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sunada
authors.affiliation: Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada T2N 4N1.
authors.forename: Hamza
authors.initials: H
authors.lastname: Riaz
authors.affiliation: Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada T2N 4N1.
authors.forename: Emily
authors.initials: E
authors.lastname: de Freitas
authors.affiliation: Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada T2N 4N1.
authors.forename: Kai
authors.initials: K
authors.lastname: Lukowiak
authors.affiliation: Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada T2N 4N1.
authors.forename: Cayley
authors.initials: C
authors.lastname: Swinton
authors.affiliation: Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada T2N 4N1.
authors.forename: Erin
authors.initials: E
authors.lastname: Swinton
authors.affiliation: Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada T2N 4N1.
authors.forename: Amy
authors.initials: A
authors.lastname: Protheroe
authors.affiliation: Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada T2N 4N1.
authors.forename: Tamila
authors.initials: T
authors.lastname: Shymansky
authors.affiliation: Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada T2N 4N1.
authors.forename: Yoshimasa
authors.initials: Y
authors.lastname: Komatsuzaki
authors.affiliation: Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada T2N 4N1 lukowiak@ucalgary.ca.
authors.forename: Ken
authors.identifier: 0000-0001-9028-1931
authors.initials: K
authors.lastname: Lukowiak
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D003216:Conditioning, Operant; D019175:DNA Methylation; D050956:HSP40 Heat-Shock Proteins / Q000378:metabolism; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000378:metabolism*; D018869:Heat-Shock Response; D006358:Hot Temperature; D008195:Lymnaea / Q000235:genetics / Q000502:physiology*; D057567:Memory, Long-Term
chemical_list: D050956:HSP40 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins
keywords: Heat shock proteins; Long-term memory; Lymnaea