Translational Enhancement via mRNA Binding to Scp160p in Yeast - Assessed by Bioinformatics and Ribosome-Affinity Purification (RAP)
Abstract
Scp160 is a yeast protein binding to over 1000 distinct mRNAs. It has been implicated in translational enhancement. Using a novel translational profiling method, RAP (Ribosome Affinity Purification), with downstream RT-qPCR detection (Reverse Transcription followed by Real-Time PCR), we were able to show that ribosme occupancy of five transcripts decreases in scp160Δ yeast compared with wild-type cells. Furthermore, using CAI (Codon Adaptation Index) and TPI (tRNA Pairing Index) in a meta-study of recent work from our group and a publication, we could show: 1) High TPI (= re-use of tRNAs bound by different isodecoding codons) is correlated with highly reproducible binding of mRNAs to Scp160p; 2) Low CAI (= use of popular codons )is correlated with mRNAs showing a shift to slow-translating polysomes in sucrose gradient fractionation assays upon SCP160 knock-down.
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