Research

The mystery of biological system achieved by RNA regulation

Genetic information embedded in our genomic DNA is first transcribed as messenger RNAs (mRNAs) and then translated to proteins. In this central dogma, you may consider mRNAs as mere intermediates of genetic information. No, they are not. Cells in our body actively degrade mRNAs and precisely control their translation to finely modulate protein expression. We combine zebrafish –a well-established model organism for genetics and developmental biology– with cutting-edge technologies such as next generation sequencing to understand basic mechanisms and principles of RNA regulation in the biological system.

A novel function of the genetic code : Codon-mediated control of mRNA stability

Translation of mRNA by the ribosome converts an array of codons into protein and therefore lies at the core of the central dogma. We discovered from zebrafish embryos that mRNA stability just after fertilization is determined by codon composition (Mishima et al., Mol Cell. 2016). This discovery indicates that translating ribosome senses the unknown difference of codons and modulates mRNA stability. However, the molecular mechanism underlying codon-mediated mRNA decay by the ribosome remains largely unknown. We aim to elucidate the molecular mechanism of codon-mediated control of mRNA stability by combining our knowledge and unique approaches established in zebrafish embryos.

Ribosomes and tRNAs：Regulation of animal development by basic translation apparatuses

Ribosomes and transfer RNAs (tRNAs) mediate translation, an essential process of life. Therefore ribosomes and tRNAs tend to be considered ubiquitous factors. However, quantity and quality of ribosomal proteins and tRNAs vary during development, among cell types and upon environmental cues. This unexpected dynamics of translation apparatus may modulate gene expression via mRNA control. We focus on highly dynamic biological processes such as animal development to test the hypothesis that ribosomes and tRNAs act as a novel layer of gene regulation.

Discovery of novel RNA regulation

Recent progresses in the RNA field draw more and more attentions from basic sciences and applied researches. There must be numbers of hidden RNA regulatory mechanisms in the complex system of life. Disruption of such mechanisms can be a threat to our health. We try to discover novel RNA regulatory mechanisms from dynamic gene regulation during animal development.