벤조피렌 노출과 온도스트레스에 의한 Scleronephthya gracillimum로부터의 Ubiquitin 유전자의 클로닝과 유전자 발현

Abstract

A cDNA clone encoding ubiquitin was isolated from a soft coral Scleronephthya gracillimum cDNA library. Ubiquitin is a small 76 amino acid protein able to attach to target proteins destined for removal. Ubiquitination serves as a recognition signal for degradation by proteasome.1) The proteasome thus is responsible for the numerous important biological processes like as stress response, DNA repair, transcriptional regulation, immune response.2) Scleronephthya gracillimum ubiquitin gene spanned 384 bp and encoded 128 amino acids showing high homology to various organisms. Northern blot analysis suggested the gene expressed as a single transcript of approximately 0.5 kb. In addition, its molecular aspects responding to ecotoxicological stress and climate change were investigated under experimental conditions. Soft coral was exposed benzo[a]pyrene (1 μM) or assigned in higher temperature (28°C) for 24 hr then RNA was extracted. RNA isolated from soft coral assigned in average seawater temperature (22°C) was compared as a control. Northern blot analysis resulted in higher level of ubiquitin mRNA expression in benzo[a]pyrene-exposed and warming-stressed groups than the average seawater temperature control. Immunobloting using anti-ubiquitin antibody resulted in various size of bands corresponding to multiple ubiquitination with substrates in benzo[a]pyrene-exposed and warming-stressed soft coral.