Transcription of the genetic code into messenger RNA (mRNA) and then translation into protein on ribosomes has to be timed correctly and the correct amount of protein produced according to the development stage. The complete process has to be above all rapid and efficient. The REGEXTRA (A novel level for the regulation of eukaryotic gene expression: coupling transcription to translation) project has studied a protein known for its role in transcription, Ctk1. Research under REGEXTRA has shown that Ctk1 interacts with another protein Sro9. Present at the site of transcription, Sro9 shuttles between the nucleus and cytoplasm and leaves the nucleus with mRNA. It could also have a place in translation. The second phase of REGEXTRA investigations revolved around 300 phosphorylated sites found on the protein building blocks of ribosomes. Ten phosphorylation sites are important in translation and details of the mechanisms of two of these have been outlined. Study of gene expression regulation is a rapidly expanding area. Applications could affect the complete range of developmental and health issues in living beings ranging from humans to microorganisms. As these mechanisms are uncovered, the reasons for the subtlety and complexity of biological systems are becoming apparent.
Transcription, translation, phosphorylation, mRNA, protein building block, Ctk1, Sro9