The Experts below are selected from a list of 288 Experts worldwide ranked by ideXlab platform
Steven Clarke - One of the best experts on this subject based on the ideXlab platform.
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histidine Methylation of yeast ribosomal Protein rpl3p is required for proper 60s subunit assembly
Molecular and Cellular Biology, 2014Co-Authors: Qais Alhadid, Kevin Roy, Guillaume Chanfreau, William Munroe, Maria C Dzialo, Steven ClarkeAbstract:Histidine Protein Methylation is an unusual posttranslational modification. In the yeast Saccharomyces cerevisiae, the large ribosomal subunit Protein Rpl3p is methylated at histidine 243, a residue that contacts the 25S rRNA near the P site. Rpl3p Methylation is dependent upon the presence of Hpm1p, a candidate seven-beta-strand methyltransferase. In this study, we elucidated the biological activities of Hpm1p in vitro and in vivo. Amino acid analyses reveal that Hpm1p is responsible for all of the detectable Protein histidine Methylation in yeast. The modification is found on a polypeptide corresponding to the size of Rpl3p in ribosomes and in a nucleus-containing organelle fraction but was not detected in Proteins of the ribosome-free cytosol fraction. In vitro assays demonstrate that Hpm1p has methyltransferase activity on ribosome-associated but not free Rpl3p, suggesting that its activity depends on interactions with ribosomal components. hpm1 null cells are defective in early rRNA processing, resulting in a deficiency of 60S subunits and translation initiation defects that are exacerbated in minimal medium. Cells lacking Hpm1p are resistant to cycloheximide and verrucarin A and have decreased translational fidelity. We propose that Hpm1p plays a role in the orchestration of the early assembly of the large ribosomal subunit and in faithful Protein production.
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histidine Methylation of yeast ribosomal Protein rpl3p is required for proper 60s subunit assembly lb185
The FASEB Journal, 2014Co-Authors: Qais Alhadid, Kevin Roy, Guillaume Chanfreau, Steven ClarkeAbstract:Histidine Protein Methylation is an unusual posttranslational modification. In the yeast Saccharomyces cerevisiae, the large ribosomal subunit Protein Rpl3p is methylated at histidine-243, a residu...
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Protein Methylation at the surface and buried deep thinking outside the histone box
Trends in Biochemical Sciences, 2013Co-Authors: Steven ClarkeAbstract:Methylated lysine and arginine residues in histones represent a crucial part of the histone code, and recognition of these methylated residues by Protein interaction domains modulates transcription. Although some methylating enzymes appear to be histone specific, many can modify histone and non-histone substrates and an increasing number are specific for non-histone substrates. Some of the non-histone substrates can also be involved in transcription, but a distinct subset of Protein Methylation reactions occurs at residues buried deeply in ribosomal Proteins that may function in Protein–RNA interactions rather than Protein–Protein interactions. Additionally, recent work has identified enzymes that catalyze Protein Methylation reactions at new sites in ribosomal and other Proteins. These reactions include modifications of histidine and cysteine residues as well as the N terminus.
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aging as war between chemical and biochemical processes Protein Methylation and the recognition of age damaged Proteins for repair
Ageing Research Reviews, 2003Co-Authors: Steven ClarkeAbstract:Deamidated, isomerized, and racemized aspartyl and asparaginyl residues represent a significant part of the spontaneous damage to Proteins that results from the aging process. The accumulation of these altered residues can lead to the loss of Protein function and the consequent loss of cellular function. However, almost all cells in nature contain a methyltransferase that can recognize the major damaged form of the L-isoaspartyl residue, and some of these enzymes can also recognize the racemized D-aspartyl residue. The methyl esterification reaction can initiate the conversion of these altered residues to the normal L-aspartyl form, although there is no evidence yet that the L-asparaginyl form can be regenerated. This enzyme, the Protein L-isoaspartate (D-aspartate) O-methyltransferase (EC 2.1.1.77), thus functions as a Protein repair enzyme. The importance of this enzyme in attenuating age-related Protein damage can be seen by the phenotypes of organisms where the gene encoding has been disrupted, or where its expression has been augmented.
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s adenosylmethionine dependent Methylation in saccharomyces cerevisiae identification of a novel Protein arginine methyltransferase
Journal of Biological Chemistry, 1999Co-Authors: Agnieszka Niewmierzycka, Steven ClarkeAbstract:We used sequence motifs conserved in S-adenosylmethionine-dependent methyltransferases to identify 26 putative methyltransferases from the complete genome of the yeast Saccharomyces cerevisiae. Seven sequences with the best matches to the methyltransferase consensus motifs were selected for further study. We prepared yeast disruption mutants of each of the genes encoding these sequences, and we found that disruption of the YJL125c gene is lethal, whereas disruptions of YCR047c and YDR140w lead to slow growth phenotypes. Normal growth was observed when the YDL201w, YDR465c, YHR209w, and YOR240w genes were disrupted. Initial analysis of Protein Methylation patterns of all mutants by amino acid analysis revealed that the YDR465c mutant has a defect in the Methylation of the delta-nitrogen atom of arginine residues. We propose that YDR465c codes for the methyltransferase responsible for this recently characterized type of Protein Methylation, and we designate the enzyme as Rmt2 (Protein arginine methyltransferase). In addition, we show that the Methylation of susceptible residues in Rmt2 substrates is likely to take place on nascent polypeptide chains and that these substrates exist in the cell as fully methylated species. Interestingly, Rmt2 has 27% sequence identity over 138 amino acids to the mammalian guanidinoacetate N-methyltransferase, an enzyme responsible for methylating the delta-nitrogen of the small molecule guanidinoacetate.
Qais Alhadid - One of the best experts on this subject based on the ideXlab platform.
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histidine Methylation of yeast ribosomal Protein rpl3p is required for proper 60s subunit assembly
Molecular and Cellular Biology, 2014Co-Authors: Qais Alhadid, Kevin Roy, Guillaume Chanfreau, William Munroe, Maria C Dzialo, Steven ClarkeAbstract:Histidine Protein Methylation is an unusual posttranslational modification. In the yeast Saccharomyces cerevisiae, the large ribosomal subunit Protein Rpl3p is methylated at histidine 243, a residue that contacts the 25S rRNA near the P site. Rpl3p Methylation is dependent upon the presence of Hpm1p, a candidate seven-beta-strand methyltransferase. In this study, we elucidated the biological activities of Hpm1p in vitro and in vivo. Amino acid analyses reveal that Hpm1p is responsible for all of the detectable Protein histidine Methylation in yeast. The modification is found on a polypeptide corresponding to the size of Rpl3p in ribosomes and in a nucleus-containing organelle fraction but was not detected in Proteins of the ribosome-free cytosol fraction. In vitro assays demonstrate that Hpm1p has methyltransferase activity on ribosome-associated but not free Rpl3p, suggesting that its activity depends on interactions with ribosomal components. hpm1 null cells are defective in early rRNA processing, resulting in a deficiency of 60S subunits and translation initiation defects that are exacerbated in minimal medium. Cells lacking Hpm1p are resistant to cycloheximide and verrucarin A and have decreased translational fidelity. We propose that Hpm1p plays a role in the orchestration of the early assembly of the large ribosomal subunit and in faithful Protein production.
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histidine Methylation of yeast ribosomal Protein rpl3p is required for proper 60s subunit assembly lb185
The FASEB Journal, 2014Co-Authors: Qais Alhadid, Kevin Roy, Guillaume Chanfreau, Steven ClarkeAbstract:Histidine Protein Methylation is an unusual posttranslational modification. In the yeast Saccharomyces cerevisiae, the large ribosomal subunit Protein Rpl3p is methylated at histidine-243, a residu...
Michael R Stallcup - One of the best experts on this subject based on the ideXlab platform.
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minireview Protein arginine Methylation of nonhistone Proteins in transcriptional regulation
Molecular Endocrinology, 2009Co-Authors: Youngho Lee, Michael R StallcupAbstract:Endocrine regulation frequently culminates in altered transcription of specific genes. The signal transduction pathways, which transmit the endocrine signal from cell surface to the transcription machinery, often involve posttranslational modifications of Proteins. Although phosphorylation has been by far the most widely studied Protein modification, recent studies have indicated important roles for other types of modification, including Protein arginine Methylation. Ten different Protein arginine methyltransferase (PRMT) family members have been identified in mammalian cells, and numerous substrates are being identified for these PRMTs. Whereas major attention has been focused on the Methylation of histones and its role in chromatin remodeling and transcriptional regulation, there are many nonhistone substrates methylated by PRMTs. This review primarily focuses on recent progress on the roles of the nonhistone Protein Methylation in transcription. Protein Methylation of coactivators, transcription factors, and signal transducers, among other Proteins, plays important roles in transcriptional regulation. Protein Methylation may affect Protein-Protein interaction, Protein-DNA or Protein-RNA interaction, Protein stability, subcellular localization, or enzymatic activity. Thus, Protein arginine Methylation is critical for regulation of transcription and potentially for various physiological/pathological processes.
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role of Protein Methylation in regulation of transcription
Endocrine Reviews, 2005Co-Authors: David Y Lee, Catherine Teyssier, Brian D Strahl, Michael R StallcupAbstract:In the last few years, the discovery of lysine and arginine Methylation in histones and other Proteins and the enzymes that carry out these posttranslational modifications has added a new dimension to the signal transduction field. In particular, there has been a huge surge in our understanding of how Methylation of nucleosomal histones at specific lysine or arginine residues affects chromatin conformations and either facilitates or inhibits transcription from neighboring genes. It appears that the responsible methyltransferases can be targeted in some cases to specific genes and in other cases to broader regions of euchromatin or heterochromatin. Methylation of histones is mechanistically linked to other types of histone modifications, such as acetylation, phosphorylation, and monoubiquitylation; combinations of these modifications cooperate to regulate chromatin structure and transcription by stimulating or inhibiting binding of specific Proteins. Although lysine Methylation has thus far been observed almost exclusively on histones, arginine Methylation has been observed on a variety of other Proteins associated with gene regulation, including DNA-binding transcriptional activators, transcriptional coactivators, and many RNA binding Proteins involved in RNA processing, transport, and stability. Thus, lysine and arginine Methylation of Proteins, like many other types of posttranslational modifications, are regulated steps of many specific signaling pathways.
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Role of Protein Methylation in chromatin remodeling and transcriptional regulation
Oncogene, 2001Co-Authors: Michael R StallcupAbstract:Recent findings suggest that lysine and arginine-specific Methylation of histones may cooperate with other types of post-translational histone modification to regulate chromatin structure and gene transcription. Proteins that methylate histones on arginine residues can collaborate with other coactivators to enhance the activity of specific transcriptional activators such as nuclear receptors. Lysine Methylation of histones is associated with transcriptionally active nuclei, regulates other types of histone modifications, and is necessary for proper mitotic cell divisions. The fact that some transcription factors and Proteins involved in RNA processing can also be methylated suggests that Protein Methylation may also contribute in other ways to regulation of transcription and post-transcriptional steps in gene regulation. In future work, it will be important to develop methods for evaluating the precise roles of Protein Methylation in the regulation of native genes in physiological settings, e.g. by using chromatin immunoprecipitation assays, differentiating cell culture systems, and genetically altered cells and animals. It will also be important to isolate additional Protein methyltransferases by molecular cloning and to characterize new methyltransferase substrates, the regulation of methyltransferase activities, and the roles of new methyltransferases and substrates.
Guillaume Chanfreau - One of the best experts on this subject based on the ideXlab platform.
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histidine Methylation of yeast ribosomal Protein rpl3p is required for proper 60s subunit assembly
Molecular and Cellular Biology, 2014Co-Authors: Qais Alhadid, Kevin Roy, Guillaume Chanfreau, William Munroe, Maria C Dzialo, Steven ClarkeAbstract:Histidine Protein Methylation is an unusual posttranslational modification. In the yeast Saccharomyces cerevisiae, the large ribosomal subunit Protein Rpl3p is methylated at histidine 243, a residue that contacts the 25S rRNA near the P site. Rpl3p Methylation is dependent upon the presence of Hpm1p, a candidate seven-beta-strand methyltransferase. In this study, we elucidated the biological activities of Hpm1p in vitro and in vivo. Amino acid analyses reveal that Hpm1p is responsible for all of the detectable Protein histidine Methylation in yeast. The modification is found on a polypeptide corresponding to the size of Rpl3p in ribosomes and in a nucleus-containing organelle fraction but was not detected in Proteins of the ribosome-free cytosol fraction. In vitro assays demonstrate that Hpm1p has methyltransferase activity on ribosome-associated but not free Rpl3p, suggesting that its activity depends on interactions with ribosomal components. hpm1 null cells are defective in early rRNA processing, resulting in a deficiency of 60S subunits and translation initiation defects that are exacerbated in minimal medium. Cells lacking Hpm1p are resistant to cycloheximide and verrucarin A and have decreased translational fidelity. We propose that Hpm1p plays a role in the orchestration of the early assembly of the large ribosomal subunit and in faithful Protein production.
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histidine Methylation of yeast ribosomal Protein rpl3p is required for proper 60s subunit assembly lb185
The FASEB Journal, 2014Co-Authors: Qais Alhadid, Kevin Roy, Guillaume Chanfreau, Steven ClarkeAbstract:Histidine Protein Methylation is an unusual posttranslational modification. In the yeast Saccharomyces cerevisiae, the large ribosomal subunit Protein Rpl3p is methylated at histidine-243, a residu...
Kevin Roy - One of the best experts on this subject based on the ideXlab platform.
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histidine Methylation of yeast ribosomal Protein rpl3p is required for proper 60s subunit assembly
Molecular and Cellular Biology, 2014Co-Authors: Qais Alhadid, Kevin Roy, Guillaume Chanfreau, William Munroe, Maria C Dzialo, Steven ClarkeAbstract:Histidine Protein Methylation is an unusual posttranslational modification. In the yeast Saccharomyces cerevisiae, the large ribosomal subunit Protein Rpl3p is methylated at histidine 243, a residue that contacts the 25S rRNA near the P site. Rpl3p Methylation is dependent upon the presence of Hpm1p, a candidate seven-beta-strand methyltransferase. In this study, we elucidated the biological activities of Hpm1p in vitro and in vivo. Amino acid analyses reveal that Hpm1p is responsible for all of the detectable Protein histidine Methylation in yeast. The modification is found on a polypeptide corresponding to the size of Rpl3p in ribosomes and in a nucleus-containing organelle fraction but was not detected in Proteins of the ribosome-free cytosol fraction. In vitro assays demonstrate that Hpm1p has methyltransferase activity on ribosome-associated but not free Rpl3p, suggesting that its activity depends on interactions with ribosomal components. hpm1 null cells are defective in early rRNA processing, resulting in a deficiency of 60S subunits and translation initiation defects that are exacerbated in minimal medium. Cells lacking Hpm1p are resistant to cycloheximide and verrucarin A and have decreased translational fidelity. We propose that Hpm1p plays a role in the orchestration of the early assembly of the large ribosomal subunit and in faithful Protein production.
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histidine Methylation of yeast ribosomal Protein rpl3p is required for proper 60s subunit assembly lb185
The FASEB Journal, 2014Co-Authors: Qais Alhadid, Kevin Roy, Guillaume Chanfreau, Steven ClarkeAbstract:Histidine Protein Methylation is an unusual posttranslational modification. In the yeast Saccharomyces cerevisiae, the large ribosomal subunit Protein Rpl3p is methylated at histidine-243, a residu...
