![Thermal biology of horseshoe crab embryos and larvae: A role for heat [An article from: Journal of Experimental Marine Biology and Ecology]](https://www.ebooknetworking.net/books/B00/0P6/bigB000P6OALE.jpg)
Thermal biology of horseshoe crab embryos and larvae: A role for heat [An article from: Journal of Experimental Marine Biology and Ecology]
Book Details
PublisherElsevier
ISBN / ASINB000P6OALE
ISBN-13978B000P6OAL6
AvailabilityAvailable for download now
MarketplaceUnited States 🇺🇸
Description
This digital document is a journal article from Journal of Experimental Marine Biology and Ecology, published by Elsevier in 2006. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.
Description:
Eggs of the American horseshoe crab, Limulus polyphemus L., develop on sandy estuarine beaches during the spring and summer, and are potentially vulnerable to thermal stress during the 3-4 weeks of development to the first instar (trilobite) larval stage. In many marine taxa, heat shock (stress) proteins (Hsp's) help individuals acclimate to stresses by restoring the proper folding of cellular proteins whose shape has been altered by temperature shock or other forms of environmental stress. We examined the survival of embryos and first instar (trilobite) larvae following heat shock, and compared the levels of Hsp70 in heat shocked and control animals. Animals acclimated to 13 or 22 ^oC had close to 100% survival when heat shocked for 3 h at 35 or 40 ^oC, but exposure to 45 ^oC for 3 h was lethal. To study the effect of heat shock on Hsp70 production under environmentally realistic conditions, animals were acclimated to either 13 or 22 ^oC, heat-shocked at 35 ^oC for 3 h, and soluble proteins were extracted following 0, 2, 4, or 6 h recovery at 22 ^oC. The relative amounts of Hsp70 in horseshoe crab embryos and larvae were examined using SDS-PAGE and Western blotting. Relative to controls animals held at a constant temperature, there was a slight elevation of Hsp70 only among heat shocked trilobite larvae in the 6 h recovery treatment. Hsp70 levels did not differ significantly between control and heat shocked embryos. Horseshoe crabs have adapted to living in a thermally stressful environment by maintaining a high baseline (constitutive) level of cellular stress proteins such as Hsp70, rather than by synthesizing inducible Hsp's when stressful temperatures are encountered. This may be an effective strategy given that the heat shocks encountered by intertidal embryos and larvae occur regularly as a function of diurnal and tidal temperature changes.
Description:
Eggs of the American horseshoe crab, Limulus polyphemus L., develop on sandy estuarine beaches during the spring and summer, and are potentially vulnerable to thermal stress during the 3-4 weeks of development to the first instar (trilobite) larval stage. In many marine taxa, heat shock (stress) proteins (Hsp's) help individuals acclimate to stresses by restoring the proper folding of cellular proteins whose shape has been altered by temperature shock or other forms of environmental stress. We examined the survival of embryos and first instar (trilobite) larvae following heat shock, and compared the levels of Hsp70 in heat shocked and control animals. Animals acclimated to 13 or 22 ^oC had close to 100% survival when heat shocked for 3 h at 35 or 40 ^oC, but exposure to 45 ^oC for 3 h was lethal. To study the effect of heat shock on Hsp70 production under environmentally realistic conditions, animals were acclimated to either 13 or 22 ^oC, heat-shocked at 35 ^oC for 3 h, and soluble proteins were extracted following 0, 2, 4, or 6 h recovery at 22 ^oC. The relative amounts of Hsp70 in horseshoe crab embryos and larvae were examined using SDS-PAGE and Western blotting. Relative to controls animals held at a constant temperature, there was a slight elevation of Hsp70 only among heat shocked trilobite larvae in the 6 h recovery treatment. Hsp70 levels did not differ significantly between control and heat shocked embryos. Horseshoe crabs have adapted to living in a thermally stressful environment by maintaining a high baseline (constitutive) level of cellular stress proteins such as Hsp70, rather than by synthesizing inducible Hsp's when stressful temperatures are encountered. This may be an effective strategy given that the heat shocks encountered by intertidal embryos and larvae occur regularly as a function of diurnal and tidal temperature changes.
