title: Heat shock protein 70 and heat shock protein 90 expression in light- and dark-adapted adult octopus retinas.
abstract: Light- and dark-adaptation leads to changes in rhabdom morphology and photopigment distribution in the octopus retina. Molecular chaperones, including heat shock proteins (Hsps), may be involved in specific signaling pathways that cause changes in photoreceptor actin- and tubulin-based cytoskeletons and movement of the photopigments, rhodopsin and retinochrome. In this study, we used immunoblotting, in situ RT-PCR, immunofluorescence and confocal microscopy to localize the inducible form of Hsp70 and the larger Hsp90 in light- and dark-adapted and dorsal and ventral halves of adult octopus retinas. The Hsps showed differences in distribution between the light and dark and in dorsal vs. ventral position in the retina. Double labeling confocal microscopy co-localized Hsp70 with actin and tubulin, and Hsp90 with the photopigment, retinochrome. Our results demonstrate the presence of Hsp70 and Hsp90 in otherwise non-stressed light- and dark-adapted octopus retinas. These Hsps may help stabilize the cytoskeleton, important for rhabdom structure, and are perhaps involved in the redistribution of retinochrome in conditions of light and dark.
authors.affiliation: Biology Department, California State University, Dominguez Hills, Carson, CA 90747, USA.
authors.forename: Gina H
authors.initials: GH
authors.lastname: Ochoa
authors.forename: Ying Mei
authors.initials: YM
authors.lastname: Clark
authors.forename: Brian
authors.initials: B
authors.lastname: Matsumoto
authors.forename: Jose A
authors.initials: JA
authors.lastname: Torres-Ruiz
authors.forename: Laura J
authors.initials: LJ
authors.lastname: Robles
mesh_terms: D000221:Adaptation, Ocular / Q000502:physiology*; D000818:Animals; D003623:Dark Adaptation / Q000502:physiology*; D005786:Gene Expression Regulation / Q000502:physiology; D018840:HSP70 Heat-Shock Proteins / Q000032:analysis / Q000096:biosynthesis*; D018841:HSP90 Heat-Shock Proteins / Q000032:analysis / Q000096:biosynthesis*; D049831:Octopodiformes; D012160:Retina / Q000737:chemistry / Q000378:metabolism*
chemical_list: D018840:HSP70 Heat-Shock Proteins; D018841:HSP90 Heat-Shock Proteins