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4v7f
From Proteopedia
Arx1 pre-60S particle.
Structural highlights
Function[RL4A_YEAST] Participates in the regulation of the accumulation of its own mRNA.[1] [RL25_YEAST] This protein binds to a specific region on the 26S rRNA. [NOG1_YEAST] Involved in the biogenesis of the 60S ribosomal subunit.[2] [IF6_YEAST] Binds to the 60S ribosomal subunit and prevents its association with the 40S ribosomal subunit to form the 80S initiation complex in the cytoplasm. Is also involved in ribosome biogenesis. Associates with pre-60S subunits in the nucleus and is involved in its nuclear export. Cytoplasmic release of TIF6 from 60S subunits and nuclear relocalization is promoted by the GTPase RIA1/EFL1 and by SDO1. Also required for pre-rRNA processing.[3] [4] [5] [6] [7] [8] [NLE1_YEAST] Involved in processing and efficient intra-nuclear transport or pre-60S ribosomal subunits. Forms a complex with REA1 which is essential for ATP-dependent dissociation of a group of nonribosomal factors from the pre-60S particle.[9] [10] [11] [ARX1_YEAST] Probable metalloprotease involved in proper assembly of pre-ribosomal particles during the biogenesis of the 60S ribosomal subunit. Accompanies the pre-60S particles to the cytoplasm.[12] [13] [RL12A_YEAST] This protein binds directly to 26S ribosomal RNA.[HAMAP-Rule:MF_00736] [RLP7_YEAST] Involved in the biogenesis of the 60S ribosomal subunit. May act as a specificity factor that binds precursor rRNAs and tethers the enzymes that carry out the early 5' to 3' exonucleolytic reactions that generate the mature rRNAs.[14] [RL11A_YEAST] Binds to 5S ribosomal RNA. [RLP24_YEAST] Involved in the biogenesis of the 60S ribosomal subunit. Ensures the docking of NOG1 to pre-60S particles.[15] [RL37A_YEAST] Binds to the 23S rRNA (By similarity). [MRT4_YEAST] Involved in mRNA turnover and ribosome assembly. [RL5_YEAST] Binds 5S RNA and is required for 60S subunit assembly. Publication Abstract from PubMedDuring eukaryotic ribosome biogenesis, nascent ribosomal RNA (rRNA) forms pre-ribosomal particles containing ribosomal proteins and assembly factors. Subsequently, these immature rRNAs are processed and remodelled. Little is known about the premature assembly states of rRNAs and their structural rearrangement during ribosome biogenesis. Using cryo-EM we characterize a pre-60S particle, where the 5S rRNA and its associated ribosomal proteins L18 and L5 (5S ribonucleoprotein (RNP)) are rotated by almost 180 degrees when compared with the mature subunit. Consequently, neighbouring 25S rRNA helices that protrude from the base of the central protuberance are deformed. This altered topology is stabilized by nearby assembly factors (Rsa4 and Nog1), which were identified by fitting their three-dimensional structures into the cryo-EM density. We suggest that the 5S RNP performs a semicircular movement during 60S biogenesis to adopt its final position, fulfilling a chaperone-like function in guiding the flanking 25S rRNA helices of the central protuberance to their final topology. 60S ribosome biogenesis requires rotation of the 5S ribonucleoprotein particle.,Leidig C, Thoms M, Holdermann I, Bradatsch B, Berninghausen O, Bange G, Sinning I, Hurt E, Beckmann R Nat Commun. 2014 Mar 24;5:3491. doi: 10.1038/ncomms4491. PMID:24662372[16] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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