Gene expression is complicated. Most research focuses on regulatory regions: promoters, enhancers and 5’ and 3’ UnTranslated Regions. However, there is still missing information: we cannot predict expression from sequence. 70% of the yeast genome is coding. To quantitatively determine how coding sequence influences gene expression we fragmented the yeast genome into 10,000 random fragments and placed each fragment under the control of an inducible (GAL1) or constitutive (RPL4A) promoter. Unsurprisingly, transcripts with premature termination codons and rare codons have lower expression.
Surprisingly, the effect of co-translational regulation of mRNA is larger when expression is driven by a constitutive promoter. To identify the molecular mechanism underlying this difference we performed a computational screen in which we analyzed thousands of RNA-seq experiments for mutants in which the difference in co-translational regulation between constitutive and inducible transcripts is lost. This screen identified an RNA helicase, which we confirmed experimentally. Our data suggest that promoter-specific co-transcriptional loading of specific RNA binding proteins attaches a signal to the mRNA that determines the coupling between translation and mRNA decay.
Cell and Developmental Biology Programme Seminar
Data i hora d'inici: 07/06/2017, 15.00h
Data i hora de fi: 07/06/2017, 17.00h
Organitzador: IRB - Institut de Recerca Biomèdica
Lloc: Edifici Clúster Laboratoris, Aula Félix Serratosa
Host: Marco Milán, IRB Barcelona & Josep Vilardell, IBMB-CSIC