The Experts below are selected from a list of 255 Experts worldwide ranked by ideXlab platform
Alan Saghatelian - One of the best experts on this subject based on the ideXlab platform.
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Data-driven synthesis of proteolysis-resistant Peptide Hormones.
Journal of the American Chemical Society, 2014Co-Authors: Michaela Prothiwa, Ismail Syed, Mark O. Huising, Talitha Van Der Meulen, Cynthia J. Donaldson, Sunia A. Trauger, Barbara B. Kahn, Alan SaghatelianAbstract:Peptide Hormones are key physiological regulators, and many would make terrific drugs; however, the therapeutic use of Peptides is limited by poor metabolism including rapid proteolysis. To develop novel proteolysis-resistant Peptide hormone analogs, we utilize a strategy that relies on data from simple mass spectrometry experiments to guide the chemical synthesis of proteolysis-resistant analogs (i.e., data-driven synthesis). Application of this strategy to oxyntomodulin (OXM), a Peptide hormone that stimulates insulin secretion from islets and lowers blood glucose in vivo, defined the OXM cleavage site in serum, and this information was used to synthesize a proteolysis-resistant OXM analog (prOXM). prOXM and OXM have similar activity in binding and glucose stimulated-insulin secretion assays. Furthermore, prOXM is also active in vivo. prOXM reduces basal glucose levels and improves glucose tolerance in mice. The discovery of prOXM suggests that proteolysis-resistant variants of other important Peptide h...
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Data-Driven Synthesis of Proteolysis-Resistant Peptide Hormones
2014Co-Authors: Michaela Prothiwa, Ismail Syed, Mark O. Huising, Cynthia J. Donaldson, Sunia A. Trauger, Barbara B. Kahn, Talitha Van Der Meulen, Alan SaghatelianAbstract:Peptide Hormones are key physiological regulators, and many would make terrific drugs; however, the therapeutic use of Peptides is limited by poor metabolism including rapid proteolysis. To develop novel proteolysis-resistant Peptide hormone analogs, we utilize a strategy that relies on data from simple mass spectrometry experiments to guide the chemical synthesis of proteolysis-resistant analogs (i.e., data-driven synthesis). Application of this strategy to oxyntomodulin (OXM), a Peptide hormone that stimulates insulin secretion from islets and lowers blood glucose in vivo, defined the OXM cleavage site in serum, and this information was used to synthesize a proteolysis-resistant OXM analog (prOXM). prOXM and OXM have similar activity in binding and glucose stimulated-insulin secretion assays. Furthermore, prOXM is also active in vivo. prOXM reduces basal glucose levels and improves glucose tolerance in mice. The discovery of prOXM suggests that proteolysis-resistant variants of other important Peptide Hormones can also be found using this strategy to increase the number of candidate therapeutic Peptides
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A peptidomics strategy to elucidate the proteolytic pathways that inactivate Peptide Hormones.
Biochemistry, 2011Co-Authors: Arthur D. Tinoco, Yun-gon Kim, Debarati M. Tagore, Jessica Wiwczar, William S. Lane, Nika N. Danial, Alan SaghatelianAbstract:Proteolysis plays a key role in regulating the levels and activity of Peptide Hormones. Characterization of the proteolytic pathways that cleave Peptide Hormones is of basic interest and can, in some cases, spur the development of novel therapeutics. The lack, however, of an efficient approach to identify endogenous fragments of Peptide Hormones has hindered the elucidation of these proteolytic pathways. Here, we apply a mass spectrometry (MS) based peptidomics approach to characterize the intestinal fragments of Peptide histidine isoleucine (PHI), a hormone that promotes glucose-stimulated insulin secretion (GSIS). Our approach reveals a proteolytic pathway in the intestine that truncates PHI at its C-terminus to produce a PHI fragment that is inactive in a GSIS assay, a result that provides a potential mechanism of PHI regulation in vivo. Differences between these in vivo peptidomics studies and in vitro lysate experiments, which showed N- and C-terminal processing of PHI, underscore the effectiveness of this approach to discover physiologically relevant proteolytic pathways. Moreover, integrating this peptidomics approach with bioassays (i.e., GSIS) provides a general strategy to reveal proteolytic pathways that may regulate the activity of Peptide Hormones.
Yoshikatsu Matsubayashi - One of the best experts on this subject based on the ideXlab platform.
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Exploring Peptide Hormones in plants: identification of four Peptide hormone-receptor pairs and two post-translational modification enzymes
Proceedings of the Japan Academy. Series B Physical and biological sciences, 2018Co-Authors: Yoshikatsu MatsubayashiAbstract:The identification of Hormones and their receptors in multicellular organisms is one of the most exciting research areas and has lead to breakthroughs in understanding how their growth and development are regulated. In particular, Peptide Hormones offer advantages as cell-to-cell signals in that they can be synthesized rapidly and have the greatest diversity in their structure and function. Peptides often undergo post-translational modifications and proteolytic processing to generate small oligoPeptide Hormones. In plants, such small post-translationally modified Peptides constitute the largest group of Peptide Hormones. We initially explored this type of Peptide hormone using bioassay-guided fractionation and later by in silico gene screening coupled with biochemical Peptide detection, which led to the identification of four types of novel Peptide Hormones in plants. We also identified specific receptors for these Peptides and transferases required for their post-translational modification. This review summarizes how we discovered these Peptide hormone-receptor pairs and post-translational modification enzymes, and how these molecules function in plant growth, development and environmental adaptation.
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Post-translational modifications in secreted Peptide Hormones in plants
Plant & cell physiology, 2010Co-Authors: Yoshikatsu MatsubayashiAbstract:More than a dozen secreted Peptides are now recognized as important Hormones that coordinate and specify cellular functions in plants. Recent evidence has shown that secreted Peptide Hormones often undergo post-translational modification and proteolytic processing, which are critical for their function. Such 'small post-translationally modified Peptide Hormones' constitute one of the largest groups of Peptide Hormones in plants. This short review highlights recent progress in research on post-translationally modified Peptide Hormones, with particular emphasis on their structural characteristics and modification mechanisms.
Michaela Prothiwa - One of the best experts on this subject based on the ideXlab platform.
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Data-driven synthesis of proteolysis-resistant Peptide Hormones.
Journal of the American Chemical Society, 2014Co-Authors: Michaela Prothiwa, Ismail Syed, Mark O. Huising, Talitha Van Der Meulen, Cynthia J. Donaldson, Sunia A. Trauger, Barbara B. Kahn, Alan SaghatelianAbstract:Peptide Hormones are key physiological regulators, and many would make terrific drugs; however, the therapeutic use of Peptides is limited by poor metabolism including rapid proteolysis. To develop novel proteolysis-resistant Peptide hormone analogs, we utilize a strategy that relies on data from simple mass spectrometry experiments to guide the chemical synthesis of proteolysis-resistant analogs (i.e., data-driven synthesis). Application of this strategy to oxyntomodulin (OXM), a Peptide hormone that stimulates insulin secretion from islets and lowers blood glucose in vivo, defined the OXM cleavage site in serum, and this information was used to synthesize a proteolysis-resistant OXM analog (prOXM). prOXM and OXM have similar activity in binding and glucose stimulated-insulin secretion assays. Furthermore, prOXM is also active in vivo. prOXM reduces basal glucose levels and improves glucose tolerance in mice. The discovery of prOXM suggests that proteolysis-resistant variants of other important Peptide h...
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Data-Driven Synthesis of Proteolysis-Resistant Peptide Hormones
2014Co-Authors: Michaela Prothiwa, Ismail Syed, Mark O. Huising, Cynthia J. Donaldson, Sunia A. Trauger, Barbara B. Kahn, Talitha Van Der Meulen, Alan SaghatelianAbstract:Peptide Hormones are key physiological regulators, and many would make terrific drugs; however, the therapeutic use of Peptides is limited by poor metabolism including rapid proteolysis. To develop novel proteolysis-resistant Peptide hormone analogs, we utilize a strategy that relies on data from simple mass spectrometry experiments to guide the chemical synthesis of proteolysis-resistant analogs (i.e., data-driven synthesis). Application of this strategy to oxyntomodulin (OXM), a Peptide hormone that stimulates insulin secretion from islets and lowers blood glucose in vivo, defined the OXM cleavage site in serum, and this information was used to synthesize a proteolysis-resistant OXM analog (prOXM). prOXM and OXM have similar activity in binding and glucose stimulated-insulin secretion assays. Furthermore, prOXM is also active in vivo. prOXM reduces basal glucose levels and improves glucose tolerance in mice. The discovery of prOXM suggests that proteolysis-resistant variants of other important Peptide Hormones can also be found using this strategy to increase the number of candidate therapeutic Peptides
Shinichiro Sawa - One of the best experts on this subject based on the ideXlab platform.
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Diverse function of plant Peptide Hormones in local signaling and development.
Current opinion in plant biology, 2019Co-Authors: Yuki Hirakawa, Shinichiro SawaAbstract:Peptide Hormones have emerged as an important class of signaling molecules that mediate developmental signals between plant cells. Membrane-bound receptors bind specific extracellular Peptide ligands to mediate communication between cells. In this review, we summarize novel Peptide Hormones identified in recent studies with an emphasis on their molecular structures. By focusing on the CLE family Peptides, we will describe the details of their physiological roles in various plant species, which include Arabidopsis, crop species, and bryophyte models.
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The roles of Peptide Hormones during plant root development.
Current opinion in plant biology, 2012Co-Authors: Masashi Yamada, Shinichiro SawaAbstract:Peptide Hormones are a key mechanism that plants use for cell-cell interactions; these interactions function to coordinate development, growth, and environmental responses among different cells. Peptide signals are produced by one cell and received by receptors in neighboring cells. It has previously been reported that Peptide Hormones regulate various aspects of plant development. The mechanism of action of Peptides in the shoot is well known. However, the function of Peptides in the root has been relatively uncharacterized. Recent studies have discovered important roles for Peptide Hormones in the development of the root meristem, lateral roots, and nodules. In this review, we focus on current findings regarding the function of Peptide Hormones in root development.
Zhan-yun Guo - One of the best experts on this subject based on the ideXlab platform.
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Bioluminescent Ligand-Receptor Binding Assays for Protein or Peptide Hormones.
Methods in molecular biology (Clifton N.J.), 2016Co-Authors: Ya-li Liu, Zhan-yun GuoAbstract:Bioluminescence has been widely used in biomedical research due to its high sensitivity, low background, and broad linear range. In recent studies, we applied bioluminescence to ligand-receptor binding assays for some protein or Peptide Hormones based on a newly developed small monomeric Nanoluciferase (NanoLuc) reporter that has the so far brightest bioluminescence. The conventional ligand-receptor binding assays rely on radioligands that have drawbacks, such as radioactive hazards and short shelf lives. In contrast, the novel bioluminescent binding assays use the NanoLuc-based protein or Peptide tracers that are safe, stable, and ultrasensitive. Thus, the novel bioluminescent ligand-receptor binding assay would be applied to more and more protein or Peptide Hormones for ligand-receptor interaction studies in future. In the present article, we provided detailed protocols for setting up the novel bioluminescent ligand-receptor binding assays using two representative protein Hormones as examples.
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Novel bioluminescent binding assays for interaction studies of protein/Peptide Hormones with their receptors
Amino acids, 2016Co-Authors: Ya-li Liu, Zhan-yun GuoAbstract:Protein/Peptide Hormones are the largest group of endogenous signaling molecules and exert various biological functions by binding to specific cell membrane receptors. To study the interactions between these Hormones and their receptors, quantitative ligand–receptor binding assays have been widely used for decades. However, the assays conventionally relied on the use of radioligands, which have some major drawbacks and can only be used in laboratories with a radioactive material license. We recently developed novel bioluminescent binding assays for several protein/Peptide Hormones using the brightest bioluminescent reporter known to date, nanoluciferase (NanoLuc). The NanoLuc reporter can be either chemically conjugated to an appropriate position, or genetically fused at one terminus, of protein/Peptide Hormones. Compared to conventional radioligands, these bioluminescent ligands have higher sensitivity, better safety, and longer shelf lives, and thus, represent a novel class of non-radioactive tracers for quantitative receptor binding assays. In the present review, we provide some general considerations and specific examples for setting up the bioluminescent binding assays. Such techniques can be applied to other protein/Peptide Hormones in future to facilitate their interaction studies with their receptors.
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Novel bioluminescent receptor-binding assays for Peptide Hormones: using ghrelin as a model.
Amino acids, 2015Co-Authors: Yu Liu, Ya-li Liu, Xiao-xia Shao, Lei Zhang, Ge Song, Zhan-yun GuoAbstract:Peptide Hormones perform important biological functions by binding specific cell membrane receptors. For hormone–receptor interaction studies, receptor-binding assays are widely used. However, conventional receptor-binding assays rely on radioactive tracers that have drawbacks. In recent studies, we established novel non-radioactive receptor-binding assays for some recombinant protein Hormones based on the ultrasensitive bioluminescence of a newly developed nanoluciferase (NanoLuc) reporter. In the present work, we extended the novel bioluminescent receptor-binding assay to Peptide Hormones that have small size and can be conveniently prepared by chemical synthesis. Human ghrelin, a 28-amino acid Peptide hormone carrying a special O-fatty acid modification, was used as a model. To prepare a bioluminescent ghrelin tracer, a chemically synthesized ghrelin analog with a unique cysteine residue at the C-terminus was site-specifically conjugated with an engineered NanoLuc with a unique exposed cysteine residue at the C-terminus via a reversible disulfide linkage. The NanoLuc-conjugated ghrelin retained high binding affinity with the ghrelin receptor GHSR1a (Kd = 1.14 ± 0.13 nM, n = 3) and was able to sensitively monitor the receptor-binding of various GHSR1a ligands. The novel bioluminescent receptor-binding assay will facilitate the interaction studies of ghrelin with its receptor. We also proposed general procedures for convenient conjugation of other Peptide Hormones with NanoLuc for novel bioluminescent receptor-binding assays.