Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0162871 (abdominal aortic aneurysm)
 8,664 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Methylation at arginines has recently come to attention as a posttranslational modification of proteins, which is implicated in processes from signaling, transcriptional activation, to mRNA processing. Here we report that several proteins extracted from HeLa cells were methylated by PRMT1 (protein arginine N-methyltransferease 1) even on a nitrocellulose membrane, while proteins from Escherichia coli are not methylated with this protein. Screening PRMT1 substrates from a lambdagt11-HeLa cDNA library, we found that more than half of the 48 cDNA clones obtained encode putative RNA-binding proteins that have RGG (arginine-glycine-glycine) motifs, such as hnRNP R (heterogeneous nuclear ribonucleoprotein R) and hnRNP K. We cloned two novel arginine methylation substrates, ZF5 (zinc finger 5) and p137GPI (GPI-anchor protein p137), which do not possess typical RGG motifs. We also cloned a novel protein that has RGG motifs, but does not have any other RNA-binding motifs. We tentatively termed this clone SAMT1 (substrate of arginine methyl transferase 1). A(63-)VLD(-65) to AAA mutation of PRMT1 suppressed the methylation of recombinant SAMT1 and other RGG proteins in the HeLa extracts. This systematic screening of substrate proteins with the solid phase methylation reaction will contribute to identify new roles of PRMT family.
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PMID:Identification of methylated proteins by protein arginine N-methyltransferase 1, PRMT1, with a new expression cloning strategy. 1218 49

During the development of transformability (competence), Bacillus subtilis synthesizes a set of proteins that mediate both the uptake of DNA at the cell poles and the recombination of this DNA with the resident chromosome. Most, if not all, of these Com proteins localize to the poles of the cell, where they associate with one another, and are then seen to delocalize as transformability declines. In this study, we use fluorescence microscopy to analyse the localization and delocalization processes. We show that localization most likely occurs by a diffusion-capture mechanism, not requiring metabolic energy, whereas delocalization is prevented in the presence of sodium azide. The kinetics of localization suggest that this process requires the synthesis of a critical protein or set of proteins, which are needed to anchor the Com protein complex to the poles. We further show that the protein kinase proteins McsA and McsB are needed for delocalization, as are ClpP and either of the AAA(+) (ATPases associated with a variety of cellular activities) proteins ClpC or ClpE. Of these proteins, at least McsB, ClpC and ClpP localize to the cell poles of competent cells. Our evidence strongly suggests that delocalization depends on the degradation of the postulated anchor protein(s) by the McsA-McsB-(ClpC or ClpE)-ClpP protease in an ATP-dependent process that involves the autophosphorylation of McsB. The extent of cell-pole association at any given time reflects the relative rates of localization and delocalization. The kinetics of this dynamic process differs for individual Com proteins, with the DNA-binding proteins SsbB and DprA exhibiting less net localization.
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PMID:McsA and B mediate the delocalization of competence proteins from the cell poles of Bacillus subtilis. 1922 26

Pex1p and Pex6p are two AAA-ATPases required for biogenesis of peroxisomes. Both proteins form a hetero-hexameric complex in an ATP-dependent manner, which has a dual localization in the cytosol and at the peroxisomal membrane. At the peroxisomal membrane, the complex is responsible for the release of the import receptor Pex5p at the end of the matrix protein import cycle. In this study, we analyzed the recruitment of the AAA-complex to its anchor protein Pex15p at the peroxisomal membrane. We show that the AAA-complex is properly assembled even under ADP-conditions and is able to bind efficiently to Pex15p in vivo. We reconstituted binding of the Pex1/6p-complex to Pex15p in vitro and show that Pex6p mediates binding to the cytosolic part of Pex15p via a direct interaction. Analysis of the isolated complex revealed a stoichiometry of Pex1p/Pex6p/Pex15p of 3:3:3, indicating that each Pex6p molecule of the AAA-complex binds Pex15p. Binding of the AAA-complex to Pex15p in particular and to the import machinery in general is stabilized when ATP is bound to the second AAA-domain of Pex6p and its hydrolysis is prevented. The data indicate that receptor release in peroxisomal protein import is associated with a nucleotide-depending Pex1/6p-cycle of Pex15p-binding and release.
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PMID:Nucleotide-dependent assembly of the peroxisomal receptor export complex. 2684 48