High-resolution view of the yeast meiotic program revealed by ribosome profiling

Meiosis is a complex developmental process that generates haploid cells from diploid progenitors. We measured mRNA abundance and protein production through yeast sporulation and found strong temporal control for most genes, achieved through both mRNA levels and translational regulation. Monitoring the timing of protein production revealed novel factors involved in recombination and helped to illuminate the molecular basis of the broad restructuring of meiotic cells. We also found a strong increase in noncanonical translation at short open reading frames (sORFs) on unannnotated transcripts and upstream regions of known transcripts (uORFs). Ribosome occupancy at near-cognate uORFs was associated with more efficient ORF translation; while some AUG uORFs, often on regulated leader extensions, acted comptetitively. This work reveals a pervasive role for meiotic translational control and great complexity in genomic coding. Fine mapping of gene expression through meiosis reveals extensive regulation of protein synthesis and widespread non-canonical translation.