Differences in heat shock protein 70 expression during larval and early spat development in the Eastern oyster, Crassostrea virginica (Gmelin, 1791)

Abstract

For a variety of species, changes in the expression of heat shock proteins (HSP) have been linked to key developmental changes, i.e., gametogenesis, embryogenesis, and metamorphosis. Many marine invertebrates are known to have a biphasic life cycle where pelagic larvae go through settlement and metamorphosis as they transition to the benthic life stage. A series of experiments were run to examine the expression of heat shock protein 70 (HSP 70) during larval and early spat (initial benthic phase) development in the Eastern oyster, Crassostrea virginica. In addition, the impact of thermal stress on HSP 70 expression during these early stages was studied. C. virginica larvae and spat expressed three HSP 70 isoforms, two constitutive, HSC 77 and HSC 72, and one inducible, HSP 69. We found differences in the expression of both the constitutive and inducible forms of HSP 70 among larval and early juvenile stages and in response to thermal stress. Low expression of HSP 69 during early larval and spat development may be associated with the susceptibility of these stages to environmental stress. Although developmental regulation of HSP 70 expression has been widely recognized, changes in its expression during settlement and metamorphosis of marine invertebrates are still unknown. The results of the current study demonstrated a reduction of HSP 70 expression during settlement and metamorphosis in the Eastern oyster, C. virginica. Keywords

Effect of pH on Gene Expression and Thermal Tolerance of Early Life History Stages of Red Abalone (Haliotis rufescens)

“…The difference in survivorship across development suggests that some developmental stages may be more sensitive than others to pH changes. Notably, the pretorsion stage may be more vulnerable to lower pH because these larvae are about to begin a major developmental transition and undergo torsion, therefore making them more sensitive to environmental perturbations (Collin & Voltzow 1998, Mahroof et al 2005, Gunter & Degnan 2007, Jardillier et al 2008, Ueda & Boettcher 2009). The same could be true for late-veliger-stage larvae.…”

Plasticity of life-cycle, physiological thermal traits and Hsp70 gene expression in an insect along the ontogeny: Effect of temperature variability

“…through antifreeze proteins; see Strom et al, 2005) and therefore it is possible that many genes could be involved in this process. In fact, several species have shown the presence of more than one heat-inducible Hsp70 gene in the same organism (Artavanis-Tsakonas et al, 1979;Lindquist, 1986;Ueda and Boettcher, 2009) that can be switched in the life-cycle of an individual. We cannot discard that other members of the Hsp gene family could be acting in the observed responses, and future experiments should analyze a broad spectrum of gene expression under temperature variable environments.…”

“…When the chaperon protein and gene expression pattern was analyzed in another tenebrionid (Tribolium castaneum), gene expression was down regulated in old larvae and was expressed to high levels in adult stage (Mahroof et al, 2005). The expression of Hsp70 has also been shown to vary during development in several species in different directions (Chang, 2005;Dix, 1997;Feder and Hofmann, 1999;Giudice et al, 1999;Karouna-Renier et al, 2003;Mahroof et al, 2005;Ueda and Boettcher, 2009;Wood et al, 1999;Yeh and Hsu, 2002). Moreover, it has been shown in a migratory locust that phenotypic variation of thermotolerance (i.e.…”

Morphology is dead – long live morphology! Integrating MorphoEvoDevo into molecular EvoDevo and phylogenomics

“…This includes morphodynamic movements and rearrangements of cells during embryogenesis, as well as patterning processes responsible for cell and tissue identity, that generate these morphological characters during ontogeny. The picture becomes even more complicated if the dynamics of gene activities, that are often important to generate entire morphological units, such as the "segmentation clock" in arthropods and vertebrates (e.g., Palmeirim et al, 1997;Sarrazin et al, 2012), or environmentally-driven plasticity of gene expression patterns [e.g., temperature-dependent regulation of segment numbers in arthropods (Vedel et al, 2008) as well as organogenesis and metamorphosis by altered expression levels of heat shock proteins in marine invertebrates (Ueda and Boettcher, 2009;Ueda and Degnan, 2013)], are consideredphenomena that are nowadays often analyzed in a framework termed "EcoEvoDevo" (see Gilbert and Epel, 2015 for a recent, in-depth treatment of the subject).…”