RNA 5'end sequencing in polysome profiling fractions

It has been shown that in mammalian cells alternative transcription initiation is extensively regulated during development and across cell-types, which confers dynamic transcript 5'UTR repertoire. However it is underexplored how the heterogeneity of 5'UTR isoforms would affect the downstream steps for protein expression, such as translation. To this end, we globally compared the translational profile of distinct mRNA TSS isoforms in mouse fibroblast cells, by combining deep-sequencing based mRNA 5'ends profiling and polysome fractionation. We demonstrated the extensive translation regulation conferred by TSS heterogeneity. Overall design: 5'end sequencing in seven polysome fractions, in two replicates, using Illumina Hiseq2000