Transcription, translation and degradation linked in protein production
Gene transcription where the DNA code is copied to RNA is relatively well understood. A big question mark still surrounds modulation and regulation of translation – from the messenger RNA (mRNA) to the protein. The EU-funded ERNBPTC (Expression regulatory networks: beyond promoters and transcription control) project used bacteria, yeast and human cells to study the interrelationships between transcription, transcription degradation and translation. The team applied experimental genomics, bioinformatics and modelling to discover several new control elements. Researchers found an efficiency design principle that helps decode the mRNA and produce a protein. The system involves protein encoding with codons that are in line with low abundance transfer RNAs (tRNAs). In mammals, another control mechanism involves two distinct sets of tRNA and codons depending on whether cells are dividing rapidly, proliferating or differentiating. Cancer is attributed to the proliferation programme. Other significant mechanisms discovered affect the control of the transcriptome in response to stress and a new sequence language that affects gene expression. There is also a process whereby the ribosome position can affect the pattern of cleavage to produce processed RNA molecules from larger RNA transcripts. Applications for ERNBPTC research results are wide-ranging. Regulation of the expression of the genome is essential under times of stress and environmental change. On a longer timescale, the work could enlighten researchers as to when these different interlinked mechanisms evolved.
Keywords
Transcription, translation, degradation, protein production, mRNA, tRNA, stress, environmental change
