Author/Editor     Koehler, Heinz-R; Belitz, Beatrix; Eckwert, Helga; Adam, Ralf; Rahman, Basim; Trontelj, Peter
Title     Validation of hsp70 stress gene expression as a marker of metal effects in Deroceras reticulatum (Pulmonata): correlation with demographic parameters
Type     članek
Source     Environ Toxicol Chem
Vol. and No.     Letnik 17, št. 11
Publication year     1998
Volume     str. 2246-53
Language     eng
Abstract     The presence of a stress gene comprising a motif homologous to the hsp70 consensus sequence was proven for the grey garden slug. Deroceras reticulatum (Mueller). The induction of stress gene transcription (including mRNA stability) and the accumulation of the corresponding stress protein, Hsp70, was quantified inslugs exposed to cadmium- or zinc-enriched food for 2 to 3 weeks. To validate the suitability of these two aspects of the cellular stress reponse to act as early-warning markers for metal effects on life-history parameters, fecundity, offspring number, longevity, and mortality of slugs were recorded in life-cycle experiments. Quantitative reverse transscription-polymerase chain reaction and a standardized immunoblotting technique revealed higher sensitivity of changes in hsp70 transcription than stress protein accumulation in response to both metals. THe elevation of the hsp70-mRNA level caused by short-term (14 d) metal exposure coincided with both diminished fecundity and reduced offspring production due to chronic metal exposure in terms of threshold concentrations for cadmium (-0.2 mg/kg) and zinc (-200 mg/kg) effects. As well, accumulation of Hsp 70 after 3 weeks of exposure can be considered an early-warning for increaed mortality when cadmium (threshold concentration -0.3-2 mg.kg) or zinc exposure (threshold concentration -0.4-2 g/kg) is throughout the entire lifetime of the slugs.
Descriptors     OLIGOCHAETA
CADMIUM CHLORIDE
ZINC
HEAT-SHOCK PROTEINS
TRANSCRIPTION, GENETIC
WATER POLLUTANTS, CHEMICAL
RNA, MESSENGER
HEAT-SHOCK PROTEINS 70
POLYMERASE CHAIN REACTION
BASE SEQUENCE
DNA, COMPLEMENTARY