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Full-Text Articles in Life Sciences
Mechanisms Underlying Insect Freeze Tolerance., Jantina Toxopeus, Brent J Sinclair
Mechanisms Underlying Insect Freeze Tolerance., Jantina Toxopeus, Brent J Sinclair
Biology Publications
Freeze tolerance - the ability to survive internal ice formation - has evolved repeatedly in insects, facilitating survival in environments with low temperatures and/or high risk of freezing. Surviving internal ice formation poses several challenges because freezing can cause cellular dehydration and mechanical damage, and restricts the opportunity to metabolise and respond to environmental challenges. While freeze-tolerant insects accumulate many potentially protective molecules, there is no apparent 'magic bullet' - a molecule or class of molecules that appears to be necessary or sufficient to support this cold-tolerance strategy. In addition, the mechanisms underlying freeze tolerance have been minimally explored. Herein, …
N-Glycosylation Regulates Pannexin 2 Localization But Is Not Required For Interacting With Pannexin 1., Rafael E Sanchez-Pupo, Danielle Johnston, Silvia Penuela
N-Glycosylation Regulates Pannexin 2 Localization But Is Not Required For Interacting With Pannexin 1., Rafael E Sanchez-Pupo, Danielle Johnston, Silvia Penuela
Anatomy and Cell Biology Publications
Pannexins (Panx1, 2, 3) are channel-forming glycoproteins expressed in mammalian tissues. We previously reported that N-glycosylation acts as a regulator of the localization and intermixing of Panx1 and Panx3, but its effects on Panx2 are currently unknown. Panx1 and Panx2 intermixing can regulate channel properties, and both pannexins have been implicated in neuronal cell death after ischemia. Our objectives were to validate the predicted N-glycosylation site of Panx2 and to study the effects of Panx2 glycosylation on localization and its capacity to interact with Panx1. We used site-directed mutagenesis, enzymatic de-glycosylation, cell-surface biotinylation, co-immunoprecipitation, and confocal microscopy. Our results showed …
The Effect Of Cold Acclimation On Active Ion Transport In Cricket Ionoregulatory Tissues., Lauren E Des Marteaux, Soheila Khazraeenia, Gil Y Yerushalmi, Andrew Donini, Natalia G Li, Brent J Sinclair
The Effect Of Cold Acclimation On Active Ion Transport In Cricket Ionoregulatory Tissues., Lauren E Des Marteaux, Soheila Khazraeenia, Gil Y Yerushalmi, Andrew Donini, Natalia G Li, Brent J Sinclair
Biology Publications
Cold-acclimated insects defend ion and water transport function during cold exposure. We hypothesized that this is achieved via enhanced active transport. The Malpighian tubules and rectum are likely targets for such transport modifications, and recent transcriptomic studies indicate shifts in Na+-K+ ATPase (NKA) and V-ATPase expression in these tissues following cold acclimation. Here we quantify the effect of cold acclimation (one week at 12 °C) on active transport in the ionoregulatory organs of adult Gryllus pennsylvanicus field crickets. We compared primary urine production of warm- and cold-acclimated crickets in excised Malpighian tubules via Ramsay assay at a range of temperatures …
Effects Of Cold Acclimation On Rectal Macromorphology, Ultrastructure, And Cytoskeletal Stability In Gryllus Pennsylvanicus Crickets., Lauren E Des Marteaux, Joseph R Stinziano, Brent J Sinclair
Effects Of Cold Acclimation On Rectal Macromorphology, Ultrastructure, And Cytoskeletal Stability In Gryllus Pennsylvanicus Crickets., Lauren E Des Marteaux, Joseph R Stinziano, Brent J Sinclair
Biology Publications
Cold-acclimated insects maintain ion and water balance in the cold, potentially by reducing permeability or increasing diffusion distance across ionoregulatory epithelia such as the rectum. We explored whether cold acclimation induces structural modifications that minimize water and ion diffusion across the rectum and maintain rectal cell integrity. We investigated rectal structure and cytoskeletal stability in chill-susceptible adult Gryllus pennsylvanicus crickets acclimated for one week to either warm (25 °C) or cold (12 °C) conditions. After acclimation, we used light and transmission electron microscopy to examine rectal macromorphology and rectal pad paracellular ultrastructure. We also used fluorescence microscopy and a filamentous-actin …