Functional Analysis of Drosophila HSP70 Promoter with Different HSE Numbers in Human Cells

Abstract

The activation of genetic constructs including the Drosophila hsp70 promoter with four and eight HSE sequences in the regulatory region has been described in human cells. The promoter was shown to be induced at lower temperatures compared to the human hsp70 promoter. The promoter activity increased after a 60-min heat shock already at 38°C in human cells. The promoter activation was observed 24 h after heat shock for the constructs with eight HSEs, while those with four HSEs required 48 h. After transplantation of in vitro heat-shocked transfected cells, the promoter activity could be maintained for 3 days with a gradual decline. The promoter activation was confirmed in vivo without preliminary heat shock in mouse ischemic brain foci. Controlled expression of the Gdnf gene under a Drosophila hsp70 promoter was demonstrated. This promoter with four and eight HSE sequences in the regulatory region can be proposed as a regulated promoter in genetic therapeutic systems.

Synergistic effects of HSE and LTR elements from hsp70 gene promoter of Ulva prolifera (Ulvophyceae, Chlorophyta) upon temperature induction1

“…In general, this mechanism is thought to be primitive and conserved in eukaryotes, and to involve activation of HSP70 by interaction between HSF and HSE. Although the copy number of the HSE element was positively correlated with the induced strength of the hsp70 promoter (Kust et al 2014, Ortner et al 2015, no studies have reported interactions between HSE and other cisacting elements. In Uphsp70, we demonstrated that neither HSE nor LTR could solely retain the high promoter activity regardless of under heat or cold temperature.…”

“…The HSE element was detected extensively from all species except for red seaweed Pyropia perforata. Additionally, the number of HSEs in a single sequence, which significantly positively correlates with induced strength of the hsp70 promoter activity (Kust et al 2014, Ortner et al 2015, varied from zero to five with species. Within algal or plant taxa, only slight variations were detected in the core sequences of HSE element containing 10 nucleotides ( Fig.…”

“…Additionally, the number of HSEs in a single sequence, which significantly positively correlates with induced strength of the hsp70 promoter activity (Kust et al. , Ortner et al. ), varied from zero to five with species.…”

“…Although the copy number of the HSE element was positively correlated with the induced strength of the hsp70 promoter (Kust et al. , Ortner et al. ), no studies have reported interactions between HSE and other cis ‐acting elements.…”

“…The 70 kDa class of heat shock proteins (HSP70s) are encoded by a gene family in eukaryotes and are differentially expressed in response to temperature stress and other conditions that interrupt normal protein folding or favor protein denaturation (Sung et al 2001). Under heat stress, induction of HSP70s is regulated by interactions between heat shock transcription factors (HSFs) and corresponding heat shock elements (HSEs) in promoter (Sch€ offl et al 1998, Kust et al 2014.…”