Translational Control across Eukaryotes

Diversity is one of the most significant features of life. The current assessment of biodiversity on Earth reaches several millions of living species, and an unimaginable number of species that have gone extinct. Further more, diversity is ingrained in all aspects of life, namely, genetics, metabolic needs, cell complexity, body plans and organismal morphology , developmental programs, behavioral patterns, and the occupancy of ecological niches. A deep understanding of all levels of organismal diversity is necessary to obtain a profound understanding of life. For this reason, the main goal of this special issue on translational control across eukaryotes is to acknowledge and discuss recent research showing that molecular and functional diversification also exists in the translation apparatus of eukaryotes. " Translation, " that is, the process of decoding a messenger RNA to synthesize a protein by the ribosome, is a fundamental process for all forms of life. The basic components and the global process of translation in eukaryotes have been largely established upon the study of traditional, so-called model organisms. However, this long-established overemphasis on model organisms has limited our knowledge of this process to few species. In recent years, the use of modern whole-genome sequencing and high-throughput technologies to study many nonmodel eukaryotes from disparate taxa has shown that the gene diversity in nature is far more expansive than we have ever imagined. These studies have uncovered a surprising diversity in the configuration of the translation apparatus across eukaryotes. This special issue acknowledges the diversity of translation factors in different lineages, the diversity found in key elements of mRNAs and RNA-binding proteins, and the diversity found in key RNA metabolism processes coupled to translational control, such as the RNA transport and the storage and degradation of mRNAs in cytoplasmic bodies. The first tutorial article, written by the editors of this installment, introduces the global topic as well as the spirit of the issue. Firstly, it introduces the general process of translation in eukaryotes and, secondly, it reviews the current knowledge on the many components of the translation machinery that have undergone diversification across phyla. Diversification of initiation factors is perhaps the most remarkable feature of the evolution of the translation apparatus. The papers by R. review this topic in protists, the most diverse but less studied group of eukaryotes. The paper covers the role of the key initiation factors eIF4F and eIFiso4F in plants. It also traces the evolutionary …