HSP70 from the Antarctic sea urchin Sterechinus neumayeri: molecular characterization and expression in response to heat stress
|Author(s)||Gonzalez-Aravena Marcelo1, Calfio Camila1, Mercado Luis2, Morales-Lange Byron2, Bethke Jorn2, de Lorgeril Julien3, Cardenas Cesar A.1|
|Affiliation(s)||1 : Inst Antartico Chileno, Dept Cient, Lab Biorrecursos Antarticos, Plaza Munoz Gamero 1055, Punta Arenas, Chile.
2 : Pontificia Univ Catolica Valparaiso, Lab Genet & Inmunol Mol, Grp Marcadores Inmunol, Inst Biol, Ave Univ 330, Valparaiso, Chile.
3 : Univ Perpignan, IFREMER, Univ Montpellier 2, CNRS,UMR IHPE 5244, Via Domitia,Pl Eugene Bataillon CC80, F-34095 Montpellier, France.
|Source||Biological Research (0716-9760) (Soc Biolgia Chile), 2018-03 , Vol. 51 , P. 8 (10p.)|
|WOS© Times Cited||16|
|Keyword(s)||Hsp70, Coelomocytes, Antarctica, Echinoderms, Climate change|
Heat stress proteins are implicated in stabilizing and refolding denatured proteins in vertebrates and invertebrates. Members of the Hsp70 gene family comprise the cognate heat shock protein (Hsc70) and inducible heat shock protein (Hsp70). However, the cDNA sequence and the expression of Hsp70 in the Antarctic sea urchin are unknown.
We amplified and cloned a transcript sequence of 1991 bp from the Antarctic sea urchin Sterechinus neumayeri, experimentally exposed to heat stress (5 and 10 °C for 1, 24 and 48 h). RACE-PCR and qPCR were employed to determine Hsp70 gene expression, while western blot and ELISA methods were used to determine protein expression.
The sequence obtained from S. neumayeri showed high identity with Hsp70 members. Several Hsp70 family features were identified in the deduced amino acid sequence and they indicate that the isolated Hsp70 is related to the cognate heat shock protein type. The corresponding 70 kDa protein, called Sn-Hsp70, was immune detected in the coelomocytes and the digestive tract of S. neumayeri using a monospecific polyclonal antibody. We showed that S. neumayeri do not respond to acute heat stress by up-regulation of Sn-Hsp70 at transcript and protein level. Furthermore, the Sn-Hsp70 protein expression was not induced in the digestive tract.
Our results provide the first molecular evidence that Sn-Hsp70 is expressed constitutively and is non-induced by heat stress in S. neumayeri.