Congratulations to Madalena and co-authors on their paper The dynamics and functional impact of tRNA repertoires during early embryogenesis in zebrafish.
An embryo starts life with a set of RNAs and proteins from its mother. During development the embryo starts transcribing its own genes into RNA, a process known as the maternal-to-zygotic transition. The protein-coding mRNAs are translated into protein by ribosomes and transfer RNAs (tRNAs). tRNAs decode the triplet nucleotide codons of the mRNA to determine which protein subunits are added to the new protein. Codon identity is an important factor determining RNA stability. However, how the pools of tRNAs change from the initial maternal pool to the zygotic pool was unknown. In this work Madalena and colleagues profiled the tRNA pools across embryonic development in zebrafish. They found that maternal and zygotic tRNA pools are distinct. Interestingly, the transition between pools did not result in a better match to the codon content of the zygotic transcriptome. Instead, they found that global translation increases at gastrulation and sensitises decoding rates to tRNA supply. This destabilises maternal mRNAs which are enriched in slowly translated codons.
This work was a collaboration with the lab of Danny Nediakova at the MPI for Biochemistry in Munich.
