scholarly journals Protein S-palmitoylation in cellular differentiation

2017 ◽  
Vol 45 (1) ◽  
pp. 275-285 ◽  
Author(s):  
Mingzi M. Zhang ◽  
Howard C. Hang
Keyword(s):  
Posttranslational Modification ◽  
Protein Function ◽  
Cellular Differentiation ◽  
Protein S ◽  
Biological Processes ◽  
Global Studies ◽  
Technological Advances ◽  
Protein Palmitoylation ◽  
Spatiotemporal Control

Reversible protein S-palmitoylation confers spatiotemporal control of protein function by modulating protein stability, trafficking and activity, as well as protein–protein and membrane–protein associations. Enabled by technological advances, global studies revealed S-palmitoylation to be an important and pervasive posttranslational modification in eukaryotes with the potential to coordinate diverse biological processes as cells transition from one state to another. Here, we review the strategies and tools to analyze in vivo protein palmitoylation and interrogate the functions of the enzymes that put on and take off palmitate from proteins. We also highlight palmitoyl proteins and palmitoylation-related enzymes that are associated with cellular differentiation and/or tissue development in yeasts, protozoa, mammals, plants and other model eukaryotes.

scholarly journals Quantitative proteomics reveals extensive lysine ubiquitination in the Arabidopsis root proteome and uncovers novel transcription factor stability states

2021 ◽  
Author(s):  
Gaoyuan Song ◽  
Damilola Olatunji ◽  
Christian Montes ◽  
Natalie M Clark ◽  
Yunting Pu ◽  
...  
Keyword(s):  
Posttranslational Modification ◽  
Site Directed Mutagenesis ◽  
Biological Processes ◽  
Protein Activity ◽  
Helix Loop Helix ◽  
Primary Roots ◽  
Lysine Residues ◽  
Ubiquitin Proteasome ◽  
The Stability

Protein activity, abundance, and stability can be regulated by posttranslational modification including ubiquitination. Ubiquitination is conserved among eukaryotes and plays a central role in modulating cellular function and yet we lack comprehensive catalogs of proteins that are modified by ubiquitin in plants. In this study, we describe an antibody-based approach to enrich peptides containing the di-glycine (diGly) remnant of ubiquitin and coupled that with isobaric labeling to enable quantification, from up to 16-multiplexed samples, for plant tissues. Collectively, we identified 7,130 diGly-modified lysine residues sites arising from 3,178 proteins in Arabidopsis primary roots. These data include ubiquitin proteasome dependent ubiquitination events as well as ubiquitination events associated with auxin treatment. Gene Ontology analysis indicated that ubiquitinated proteins are associated with numerous biological processes including hormone signaling, plant defense, protein homeostasis, and root morphogenesis. We determined the ubiquitinated lysine residues that directly regulate the stability of the transcription factors CRYPTOCHROME-INTERACTING BASIC-HELIX-LOOP-HELIX 1 (CIB1), CIB1 LIKE PROTEIN 2 (CIL2), and SENSITIVE TO PROTON RHIZOTOXICITY (STOP1) using site directed mutagenesis and in vivo degradation assays. These comprehensive site-level ubiquitinome profiles provide a wealth of data for future studies related to modulation of biological processes mediated by this posttranslational modification in plants.

scholarly journals SwissPalm: Protein Palmitoylation database

F1000Research ◽  
2015 ◽  
Vol 4 ◽  
pp. 261 ◽  
Author(s):  
Mathieu Blanc ◽  
Fabrice David ◽  
Laurence Abrami ◽  
Daniel Migliozzi ◽  
Florence Armand ◽  
...  
Keyword(s):  
Protein S ◽  
Biological Processes ◽  
Post Translational Modification ◽  
Chemical Methods ◽  
Post Translational Modifications ◽  
P Protein ◽  
Multiple Alignments ◽  
Protein Palmitoylation ◽  
Recent Developments ◽  
Pathway Analyses

Protein S-palmitoylation is a reversible post-translational modification that regulates many key biological processes, although the full extent and functions of protein S-palmitoylation remain largely unexplored. Recent developments of new chemical methods have allowed the establishment of palmitoyl-proteomes of a variety of cell lines and tissues from different species.  As the amount of information generated by these high-throughput studies is increasing, the field requires centralization and comparison of this information. Here we present SwissPalm (http://swisspalm.epfl.ch), our open, comprehensive, manually curated resource to study protein S-palmitoylation. It currently encompasses more than 5000 S-palmitoylated protein hits from seven species, and contains more than 500 specific sites of S-palmitoylation. SwissPalm also provides curated information and filters that increase the confidence in true positive hits, and integrates predictions of S-palmitoylated cysteine scores, orthologs and isoform multiple alignments. Systems analysis of the palmitoyl-proteome screens indicate that 10% or more of the human proteome is susceptible to S-palmitoylation. Moreover, ontology and pathway analyses of the human palmitoyl-proteome reveal that key biological functions involve this reversible lipid modification. Comparative analysis finally shows a strong crosstalk between S-palmitoylation and other post-translational modifications. Through the compilation of data and continuous updates, SwissPalm will provide a powerful tool to unravel the global importance of protein S-palmitoylation.

scholarly journals Exosomes: Versatile Nano Mediators of Immune Regulation

Cancers ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 1557 ◽  
Author(s):  
Li ◽  
Wang ◽  
Peng ◽  
Huyan ◽  
Cacalano
Keyword(s):  
Cellular Differentiation ◽  
Vaccine Development ◽  
Cell Communication ◽  
Diagnostic Tools ◽  
Biological Processes ◽  
Pathological Conditions ◽  
Wide Range ◽  
Almost All ◽  
Novel Drug

One of many types of extracellular vesicles (EVs), exosomes are nanovesicle structures that are released by almost all living cells that can perform a wide range of critical biological functions. Exosomes play important roles in both normal and pathological conditions by regulating cell-cell communication in cancer, angiogenesis, cellular differentiation, osteogenesis, and inflammation. Exosomes are stable in vivo and they can regulate biological processes by transferring lipids, proteins, nucleic acids, and even entire signaling pathways through the circulation to cells at distal sites. Recent advances in the identification, production, and purification of exosomes have created opportunities to exploit these structures as novel drug delivery systems, modulators of cell signaling, mediators of antigen presentation, as well as biological targeting agents and diagnostic tools in cancer therapy. This review will examine the functions of immunocyte-derived exosomes and their roles in the immune response under physiological and pathological conditions. The use of immunocyte exosomes in immunotherapy and vaccine development is discussed.

scholarly journals Conditionally Activated (“Caged”) Oligonucleotides

Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1481
Author(s):  
Linlin Yang ◽  
Ivan J. Dmochowski
Keyword(s):  
Caspase 3 ◽  
Single Cells ◽  
Probe Design ◽  
Biological Processes ◽  
Light Activation ◽  
Efficient Synthesis ◽  
In Vivo Analysis ◽  
Physiologic Condition ◽  
Spatiotemporal Control

Conditionally activated (“caged”) oligonucleotides provide useful spatiotemporal control for studying dynamic biological processes, e.g., regulating in vivo gene expression or probing specific oligonucleotide targets. This review summarizes recent advances in caging strategies, which involve different stimuli in the activation step. Oligo cyclization is a particularly attractive caging strategy, which simplifies the probe design and affords oligo stabilization. Our laboratory developed an efficient synthesis for circular caged oligos, and a circular caged antisense DNA oligo was successfully applied in gene regulation. A second technology is Transcriptome In Vivo Analysis (TIVA), where caged oligos enable mRNA isolation from single cells in living tissue. We highlight our development of TIVA probes with improved caging stability. Finally, we illustrate the first protease-activated oligo probe, which was designed for caspase-3. This expands the toolkit for investigating the transcriptome under a specific physiologic condition (e.g., apoptosis), particularly in specimens where light activation is impractical.

scholarly journals Affimer proteins are versatile and renewable affinity reagents

eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Christian Tiede ◽  
Robert Bedford ◽  
Sophie J Heseltine ◽  
Gina Smith ◽  
Imeshi Wijetunga ◽  
...  
Keyword(s):  
Protein Function ◽  
Cell Biology ◽  
Super Resolution ◽  
Biological Processes ◽  
Affinity Reagents ◽  
Tumour Antigens ◽  
Target Molecules ◽  
Super Resolution Microscopy

Molecular recognition reagents are key tools for understanding biological processes and are used universally by scientists to study protein expression, localisation and interactions. Antibodies remain the most widely used of such reagents and many show excellent performance, although some are poorly characterised or have stability or batch variability issues, supporting the use of alternative binding proteins as complementary reagents for many applications. Here we report on the use of Affimer proteins as research reagents. We selected 12 diverse molecular targets for Affimer selection to exemplify their use in common molecular and cellular applications including the (a) selection against various target molecules; (b) modulation of protein function in vitro and in vivo; (c) labelling of tumour antigens in mouse models; and (d) use in affinity fluorescence and super-resolution microscopy. This work shows that Affimer proteins, as is the case for other alternative binding scaffolds, represent complementary affinity reagents to antibodies for various molecular and cell biology applications.

scholarly journals The SUMO-Specific Protease SENP5 Is Required for Cell Division

2006 ◽  
Vol 26 (12) ◽  
pp. 4489-4498 ◽  
Author(s):  
Alessandra Di Bacco ◽  
Jian Ouyang ◽  
Hsiang-Ying Lee ◽  
Andre Catic ◽  
Hidde Ploegh ◽  
...  
Keyword(s):  
Cell Division ◽  
Chromosome Segregation ◽  
Posttranslational Modification ◽  
Catalytic Domain ◽  
Biological Processes ◽  
Nucleocytoplasmic Trafficking ◽  
Binucleate Cells ◽  
Specific Protease

ABSTRACT Posttranslational modification of substrates by the small ubiquitin-like modifier, SUMO, regulates diverse biological processes, including transcription, DNA repair, nucleocytoplasmic trafficking, and chromosome segregation. SUMOylation is reversible, and several mammalian homologs of the yeast SUMO-specific protease Ulp1, termed SENPs, have been identified. We demonstrate here that SENP5, a previously uncharacterized Ulp1 homolog, has SUMO C-terminal hydrolase and SUMO isopeptidase activities. In contrast to other SENPs, the C-terminal catalytic domain of SENP5 preferentially processed SUMO-3 compared to SUMO-1 precursors and preferentially removed SUMO-2 and SUMO-3 from SUMO-modified RanGAP1 in vitro. In cotransfection assays, SENP5 preferentially reduced high-molecular-weight conjugates of SUMO-2 compared to SUMO-1 in vivo. Full-length SENP5 localized to the nucleolus. Deletion of the noncatalytic N-terminal domain led to loss of nucleolar localization and increased de-SUMOylation activity in vivo. Knockdown of SENP5 by RNA interference resulted in increased levels of SUMO-1 and SUMO-2/3 conjugates, inhibition of cell proliferation, defects in nuclear morphology, and appearance of binucleate cells, revealing an essential role for SENP5 in mitosis and/or cytokinesis. These findings establish SENP5 as a SUMO-specific protease required for cell division and suggest that mechanisms involving both the catalytic and noncatalytic domains determine the distinct substrate specificities of the mammalian SUMO-specific proteases.

The Anticoagulant Properties of a Modified Form of Protein S

1988 ◽  
Vol 60 (02) ◽  
pp. 298-304 ◽  
Author(s):  
C A Mitchell ◽  
S M Kelemen ◽  
H H Salem
Keyword(s):  
Monoclonal Antibody ◽  
Anticoagulant Activity ◽  
Activated Protein C ◽  
Factor Xa ◽  
Protein S ◽  
Human Neutrophil Elastase ◽  
Factor X ◽  
Sds Page

SummaryProtein S (PS) is a vitamin K-dependent anticoagulant that acts as a cofactor to activated protein C (APC). To date PS has not been shown to possess anticoagulant activity in the absence of APC.In this study, we have developed monoclonal antibody to protein S and used to purify the protein to homogeneity from plasma. Affinity purified protein S (PSM), although identical to the conventionally purified protein as judged by SDS-PAGE, had significant anticoagulant activity in the absence of APC when measured in a factor Xa recalcification time. Using SDS-PAGE we have demonstrated that prothrombin cleavage by factor X awas inhibited in the presence of PSM. Kinetic analysis of the reaction revealed that PSM competitively inhibited factor X amediated cleavage of prothrombin. PS preincubated with the monoclonal antibody, acquired similar anticoagulant properties. These results suggest that the interaction of the monoclonal antibody with PS results in an alteration in the protein exposing sites that mediate the observed anticoagulant effect. Support that the protein was altered was derived from the observation that PSM was eight fold more sensitive to cleavage by thrombin and human neutrophil elastase than conventionally purified protein S.These observations suggest that PS can be modified in vitro to a protein with APC-independent anticoagulant activity and raise the possibility that a similar alteration could occur in vivo through the binding protein S to a cellular or plasma protein.

Molecular pathways of Interferon–Stimulated Gene 15: Implications in cancer

2020 ◽  
Vol 21 ◽  
Author(s):  
Angeles C. Tecalco–Cruz
Keyword(s):  
Posttranslational Modification ◽  
Human Interferon ◽  
Molecular Pathways ◽  
Biological Processes ◽  
Small Protein ◽  
Target Proteins ◽  
Central Elements ◽  
Cancer Types ◽  
Interferon Stimulated Gene 15

Abstract:: Human interferon–stimulated gene 15 (ISG15) is a 15–kDa ubiquitin–like protein that can be detected as either free ISG15 or covalently associated with its target proteins through a process termed ISGylation. Interestingly, extracellular free ISG15 has been proposed as a cytokine–like protein, whereas ISGylation is a posttranslational modification. ISG15 is a small protein with implications in some biological processes and pathologies that include cancer. This review highlights the findings of both free ISG15 and protein ISGylation involved in several molecular pathways, emerging as central elements in some cancer types.

scholarly journals PPM1G promotes the progression of hepatocellular carcinoma via phosphorylation regulation of alternative splicing protein SRSF3

2021 ◽  
Vol 12 (8) ◽  
Author(s):  
Dawei Chen ◽  
Zhenguo Zhao ◽  
Lu Chen ◽  
Qinghua Li ◽  
Jixue Zou ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Alternative Splicing ◽  
Protein Function ◽  
Vital Role ◽  
Normal Tissues ◽  
Mechanistic Analysis ◽  
Highly Correlated ◽  
Splicing Patterns

AbstractEmerging evidence has demonstrated that alternative splicing has a vital role in regulating protein function, but how alternative splicing factors can be regulated remains unclear. We showed that the PPM1G, a protein phosphatase, regulated the phosphorylation of SRSF3 in hepatocellular carcinoma (HCC) and contributed to the proliferation, invasion, and metastasis of HCC. PPM1G was highly expressed in HCC tissues compared to adjacent normal tissues, and higher levels of PPM1G were observed in adverse staged HCCs. The higher levels of PPM1G were highly correlated with poor prognosis, which was further validated in the TCGA cohort. The knockdown of PPM1G inhibited the cell growth and invasion of HCC cell lines. Further studies showed that the knockdown of PPM1G inhibited tumor growth in vivo. The mechanistic analysis showed that the PPM1G interacted with proteins related to alternative splicing, including SRSF3. Overexpression of PPM1G promoted the dephosphorylation of SRSF3 and changed the alternative splicing patterns of genes related to the cell cycle, the transcriptional regulation in HCC cells. In addition, we also demonstrated that the promoter of PPM1G was activated by multiple transcription factors and co-activators, including MYC/MAX and EP300, MED1, and ELF1. Our study highlighted the essential role of PPM1G in HCC and shed new light on unveiling the regulation of alternative splicing in malignant transformation.

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