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The GAR domain integrates functions that are necessary for the proper localization of fibrillarin (FBL) inside eukaryotic cells.

ABSTRACT: Fibrillarin (FBL) is an essential nucleolar protein that participates in pre-rRNA methylation and processing. The methyltransferase domain of FBL is an example of an extremely well-conserved protein domain in which the amino acid sequence was not substantially modified during the evolution from Archaea to Eukaryota. An additional N-terminal glycine-arginine-rich (GAR) domain is present in the FBL of eukaryotes. Here, we demonstrate that the GAR domain is involved in FBL functioning and integrates the functions of the nuclear localization signal and the nucleolar localization signal (NoLS). The methylation of the arginine residues in the GAR domain is necessary for nuclear import but decreases the efficiency of nucleolar retention via the NoLS. The presented data indicate that the GAR domain can be considered an evolutionary innovation that integrates several functional activities and thereby adapts FBL to the highly compartmentalized content of the eukaryotic cell.

SUBMITTER: Shubina MY

PROVIDER: S-EPMC7194090 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Fibrillarin Ribonuclease Activity is Dependent on the GAR Domain and Modulated by Phospholipids.

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son is necessary for proper vertebrate blood development.

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GAR-Driven Subcellular Localization of the Growth Controlling RNA Binding Protein Nucleolin

Project description:This SuperSeries is composed of the SubSeries listed below.

2021-07-23 | GSE142576 | GEO

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