Metallothionein gene activation in the earthworm (Lumbricus rubellus)

TY - JOUR

T1 - Metallothionein gene activation in the earthworm (Lumbricus rubellus)

AU - Höckner, M.

AU - Dallinger, R.

AU - Stürzenbaum, S. R.

PY - 2015/5/8

Y1 - 2015/5/8

N2 - In order to cope with changing environmental conditions, organisms require highly responsive stress mechanisms. Heavy metal stress is handled by metallothioneins (MTs), the regulation of which is evolutionary conserved in insects and vertebrates and involves the binding of metal transcription factor 1 (MTF-1) to metal responsive elements (MREs) positioned in the promoter of MT genes. However, in most invertebrate phyla, the transcriptional activation of MTs is different and the exact mechanism is still unknown. Interestingly, although MREs are typically present also in invertebrate MT gene promoters, MTF-1 is notably absent. Here we use Lumbricus rubellus, the red earthworm, to study the elusive mechanism of wMT-2 activation in control and Cd-exposed conditions. EMSA and DNase I footprinting approaches were used to pinpoint functional binding sites within the wMT-2 promoter region, which revealed that the cAMP responsive element (CRE) is a promising candidate which may act as a transcriptional activator of invertebrate MTs.

AB - In order to cope with changing environmental conditions, organisms require highly responsive stress mechanisms. Heavy metal stress is handled by metallothioneins (MTs), the regulation of which is evolutionary conserved in insects and vertebrates and involves the binding of metal transcription factor 1 (MTF-1) to metal responsive elements (MREs) positioned in the promoter of MT genes. However, in most invertebrate phyla, the transcriptional activation of MTs is different and the exact mechanism is still unknown. Interestingly, although MREs are typically present also in invertebrate MT gene promoters, MTF-1 is notably absent. Here we use Lumbricus rubellus, the red earthworm, to study the elusive mechanism of wMT-2 activation in control and Cd-exposed conditions. EMSA and DNase I footprinting approaches were used to pinpoint functional binding sites within the wMT-2 promoter region, which revealed that the cAMP responsive element (CRE) is a promising candidate which may act as a transcriptional activator of invertebrate MTs.

KW - CREB

KW - Earthworm

KW - Gene regulation

KW - Lumbricus rubellus

KW - Metallothionein

UR - http://www.scopus.com/inward/record.url?scp=84937765055&partnerID=8YFLogxK

U2 - 10.1016/j.bbrc.2015.03.065

DO - 10.1016/j.bbrc.2015.03.065

M3 - Article

AN - SCOPUS:84937765055

SN - 0006-291X

VL - 460

SP - 537

EP - 542

JO - Biochemical and Biophysical Research Communications

JF - Biochemical and Biophysical Research Communications

IS - 3

ER -