Construção de novos termômetros para regulação da expressão gênica em Escherichia coli

Abstract

Introduction: Temperature is a critical environmental parameter constantly monitored by cells. During gene expression, certain heat shock, cold shock, and virulent genes are modulated in response to abrupt temperature changes. In bacteria, heat shock genes are regulated both transcriptionally and post-transcriptionally through temperature-sensitive RNA sequences known as RNA thermometers (RNATs). These elements modulate translation efficiency by altering the mRNA secondary structure in response to temperature changes, thereby controlling access to the ribosome binding site (RBS). RNATs are typically located in the 5′ untranslated region (5′ UTR) of mRNAs, where they form base-paired structures that occlude the RBS and/or the start codon at lower or physiological temperatures. Upon temperature elevation, structural rearrangements expose the Shine-Dalgarno sequence, allowing ribosome binding and translation initiation. Objective: To construct novel RNA thermometers through chemical synthesis of degenerate DNA sequences...