As a nucleolar complex for small-subunit (SSU) ribosomal RNA processing, SSU processome has been extensively studied mainly in Saccharomyces cerevisiae but not in diverse organisms, leaving open the question of whether it is a ubiquitous mechanism across eukaryotes and how it evolved in the course of the evolution of eukaryotes. Genome-wide survey and identification of SSU processome components showed that the majority of all 77 yeast SSU processome proteins possess homologs in almost all of the main eukaryotic lineages, and 14 of them have homologs in archaea but few in bacteria, suggesting that the complex is ubiquitous in eukaryotes, and its evolutionary history began with abundant protein homologs being present in archaea and then a fairly complete form of the complex emerged in the last eukaryotic common ancestor (LECA). Phylogenetic analysis indicated that ancient gene duplication and functional divergence of the protein components of the complex occurred frequently during the evolutionary origin of the LECA from prokaryotes. We found that such duplications not only increased the complex's components but also produced some new functional proteins involved in other nucleolar functions, such as ribosome biogenesis and even ...Continue Reading
Complementary sequences 1700 nucleotides apart form a ribonuclease III cleavage site in Escherichia coli ribosomal precursor RNA
Separate pathways for excision and processing of 16S and 23S rRNA from the primary rRNA operon transcript from the hyperthermophilic archaebacterium Sulfolobus acidocaldarius: similarities to eukaryotic rRNA processing
Ribosomal RNA precursor processing by a eukaryotic U3 small nucleolar RNA-like molecule in an archaeon
Transcription analysis of two disparate rRNA operons in the halophilic archaeon Haloarcula marismortui
Base pairing between U3 small nucleolar RNA and the 5' end of 18S rRNA is required for pre-rRNA processing.
Archaeal ribosomal protein L7 is a functional homolog of the eukaryotic 15.5kD/Snu13p snoRNP core protein
Protein 61K, encoded by a gene (PRPF31) linked to autosomal dominant retinitis pigmentosa, is required for U4/U6*U5 tri-snRNP formation and pre-mRNA splicing
Nep1p (Emg1p), a novel protein conserved in eukaryotes and archaea, is involved in ribosome biogenesis
The human Imp3 and Imp4 proteins form a ternary complex with hMpp10, which only interacts with the U3 snoRNA in 60-80S ribonucleoprotein complexes
A plant snoRNP complex containing snoRNAs, fibrillarin, and nucleolin-like proteins is competent for both rRNA gene binding and pre-rRNA processing in vitro
Imp3p and Imp4p mediate formation of essential U3-precursor rRNA (pre-rRNA) duplexes, possibly to recruit the small subunit processome to the pre-rRNA
Assessment of methods for amino acid matrix selection and their use on empirical data shows that ad hoc assumptions for choice of matrix are not justified
Small-subunit rRNA processome proteins are translationally regulated during differentiation of Trypanosoma cruzi
Alternative conformations of the archaeal Nop56/58-fibrillarin complex imply flexibility in box C/D RNPs
Recruitment of factors linking transcription and processing of pre-rRNA to NOR chromatin is UBF-dependent and occurs independent of transcription in human cells
A novel small-subunit processome assembly intermediate that contains the U3 snoRNP, nucleolin, RRP5, and DBP4
RNA chaperones stimulate formation and yield of the U3 snoRNA-Pre-rRNA duplexes needed for eukaryotic ribosome biogenesis
The initial U3 snoRNA:pre-rRNA base pairing interaction required for pre-18S rRNA folding revealed by in vivo chemical probing
Complete genome sequence of the hyperthermophilic chemolithoautotroph Pyrolobus fumarii type strain (1A)
Roles of ASYMMETRIC LEAVES2 (AS2) and Nucleolar Proteins in the Adaxial-Abaxial Polarity Specification at the Perinucleolar Region in Arabidopsis.
Recent advances in genomic sequencing has led to the discovery of new strains of Archaea and shed light on their evolutionary history. Discover the latest research on Archaeogenetics here.