Proteolytic degradation of hemoglobin in vivo. Role in formation of tissue specific peptide pool

1998 ◽  
Vol 70 (1) ◽  
pp. 67-74 ◽  
Author(s):  
Vadim T. Ivanov ◽  
Andrei A. Karelin ◽  
Elena Yu. Blischenko ◽  
Marina M. Philippova ◽  
Igor V. Nazimov
Keyword(s):  
Peptide Pool ◽  
Proteolytic Degradation ◽  
Tissue Specific ◽  
Specific Peptide

Tissue-specific peptide pools. Generation and function

2000 ◽  
Vol 72 (3) ◽  
pp. 355-363 ◽  
Author(s):  
Vadim T. Ivanov ◽  
Oleg N. Yatskin ◽  
Olga A. Kalinina ◽  
Marina M. Philippova ◽  
Andrei A. Karelin ◽  
...  
Keyword(s):  
Surrounding Medium ◽  
Regulatory System ◽  
Systematic Analysis ◽  
Tissue Specific ◽  
Tissue Extracts ◽  
Normal Ratio ◽  
And Function ◽  
Dying Cells ◽  
Specific Peptide

Systematic analysis of several tissue extracts for peptide components followed by bioactivity studies leads to formulation of the concept of "tissue-specific peptide pools". According to that concept the endogenous proteolysis of proteins with well-established functions, such as hemoglobin, actin, and cellular enzymes in tissues leads to formation of the sets (or pools) of bioactive peptides. The sets are tissue-specific on one hand and conservative in a given tissue at normal conditions on the other. The content and the composition of pool components are sensitive both to pathologies linked with alterations of tissue metabolism and to prolonged physiological changes. In vivo formation of fragments of functional proteins includes several consecutive proteolytic stages inside the cells and further release of bioactive compounds into the surrounding medium. The effects of pool components take place predominantly at tissue and cellular levels, their effects being related to stimulation or inhibition of cell growth, induction of cell differentiation, and death. The above-mentioned features lead to the proposal that the main in vivo function of components of tissue-specific peptides is maintenance of tissue homeostasis, i.e., the normal ratio of functional, dividing, differentiating, and dying cells of tissues. Components of tissue-specific peptide pools display several features distinguishing them from "classical" peptide hormones and neuromediators. Summarizing, a novel peptidergic regulatory system is considered.

GABA-induced changes of the tissue-specific peptide pool of white rat brain

2000 ◽  
Vol 6 (4) ◽  
pp. 168-174 ◽  
Author(s):  
Andrei A. Karelin ◽  
Marina M. Philippova ◽  
Elena V. Karelina ◽  
Boris N. Strizhkov ◽  
Igor V. Nazimov ◽  
...  
Keyword(s):  
Rat Brain ◽  
Peptide Pool ◽  
Tissue Specific ◽  
Induced Changes ◽  
Specific Peptide

Hemoglobin as a source of endogenous bioactive peptides: The concept of tissue-specific peptide pool

Biopolymers ◽  
1997 ◽  
Vol 43 (2) ◽  
pp. 171-188 ◽  
Author(s):  
Vadim T. Ivanov ◽  
Andrei A. Karelin ◽  
Marina M. Philippova ◽  
Igor V. Nazimov ◽  
Vladimir Z. Pletnev
Keyword(s):  
Bioactive Peptides ◽  
Peptide Pool ◽  
Tissue Specific ◽  
Specific Peptide

scholarly journals Caenorhabditis elegans Junctophilin has tissue-specific functions and regulates neurotransmission with extended-synaptotagmin

Genetics ◽  
2021 ◽  
Author(s):  
Christopher A Piggott ◽  
Zilu Wu ◽  
Stephen Nurrish ◽  
Suhong Xu ◽  
Joshua M Kaplan ◽  
...  
Keyword(s):  
Calcium Channels ◽  
Calcium Channel ◽  
Tissue Specific ◽  
Voltage Gated ◽  
Membrane Contact Sites ◽  
Contact Sites ◽  
Pharyngeal Muscles ◽  
Membrane Contact ◽  
Null Mutants

Abstract The junctophilin family of proteins tether together plasma membrane (PM) and endoplasmic reticulum (ER) membranes, and couple PM- and ER-localized calcium channels. Understanding in vivo functions of junctophilins is of great interest for dissecting the physiological roles of ER-PM contact sites. Here, we show that the sole C. elegans junctophilin JPH-1 localizes to discrete membrane contact sites in neurons and muscles and has important tissue-specific functions. jph-1 null mutants display slow growth and development due to weaker contraction of pharyngeal muscles, leading to reduced feeding. In the body wall muscle, JPH-1 co-localizes with the PM-localized EGL-19 voltage-gated calcium channel and ER-localized UNC-68/RyR calcium channel, and is required for animal movement. In neurons, JPH-1 co-localizes with the membrane contact site protein Extended-SYnaptoTagmin 2 (ESYT-2) in soma, and is present near presynaptic release sites. Interestingly, jph-1 and esyt-2 null mutants display mutual suppression in their response to aldicarb, suggesting that JPH-1 and ESYT-2 have antagonistic roles in neuromuscular synaptic transmission. Additionally, we find an unexpected cell non-autonomous effect of jph-1 in axon regrowth after injury. Genetic double mutant analysis suggests that jph-1 functions in overlapping pathways with two PM-localized voltage-gated calcium channels, egl-19 and unc-2, and unc-68/RyR for animal health and development. Finally, we show that jph-1 regulates the colocalization of EGL-19 and UNC-68 and that unc-68/RyR is required for JPH-1 localization to ER-PM puncta. Our data demonstrate important roles for junctophilin in cellular physiology, and also provide insights into how junctophilin functions together with other calcium channels in vivo.

scholarly journals The Radiation-Induced Regenerative Response of Adult Tissue-Specific Stem Cells: Models and Signaling Pathways

Cancers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 855
Author(s):  
Paola Serrano Martinez ◽  
Lorena Giuranno ◽  
Marc Vooijs ◽  
Robert P. Coppes
Keyword(s):  
Signaling Pathways ◽  
Progenitor Cells ◽  
Tissue Regeneration ◽  
Normal Tissue ◽  
Cellular Response ◽  
Adult Tissue ◽  
Tissue Specific ◽  
Radiation Induced

Radiotherapy is involved in the treatment of many cancers, but damage induced to the surrounding normal tissue is often inevitable. Evidence suggests that the maintenance of homeostasis and regeneration of the normal tissue is driven by specific adult tissue stem/progenitor cells. These tasks involve the input from several signaling pathways. Irradiation also targets these stem/progenitor cells, triggering a cellular response aimed at achieving tissue regeneration. Here we discuss the currently used in vitro and in vivo models and the involved specific tissue stem/progenitor cell signaling pathways to study the response to irradiation. The combination of the use of complex in vitro models that offer high in vivo resemblance and lineage tracing models, which address organ complexity constitute potential tools for the study of the stem/progenitor cellular response post-irradiation. The Notch, Wnt, Hippo, Hedgehog, and autophagy signaling pathways have been found as crucial for driving stem/progenitor radiation-induced tissue regeneration. We review how these signaling pathways drive the response of solid tissue-specific stem/progenitor cells to radiotherapy and the used models to address this.

scholarly journals Compensation mechanism in tumor cell migration

2003 ◽  
Vol 160 (2) ◽  
pp. 267-277 ◽  
Author(s):  
Katarina Wolf ◽  
Irina Mazo ◽  
Harry Leung ◽  
Katharina Engelke ◽  
Ulrich H. von Andrian ◽  
...  
Keyword(s):  
Cell Migration ◽  
Tumor Cell ◽  
Shape Change ◽  
Proteolytic Degradation ◽  
Amoeboid Movement ◽  
Tumor Cell Migration ◽  
Tumor Dissemination ◽  
Β1 Integrins

Invasive tumor dissemination in vitro and in vivo involves the proteolytic degradation of ECM barriers. This process, however, is only incompletely attenuated by protease inhibitor–based treatment, suggesting the existence of migratory compensation strategies. In three-dimensional collagen matrices, spindle-shaped proteolytically potent HT-1080 fibrosarcoma and MDA-MB-231 carcinoma cells exhibited a constitutive mesenchymal-type movement including the coclustering of β1 integrins and MT1–matrix metalloproteinase (MMP) at fiber bindings sites and the generation of tube-like proteolytic degradation tracks. Near-total inhibition of MMPs, serine proteases, cathepsins, and other proteases, however, induced a conversion toward spherical morphology at near undiminished migration rates. Sustained protease-independent migration resulted from a flexible amoeba-like shape change, i.e., propulsive squeezing through preexisting matrix gaps and formation of constriction rings in the absence of matrix degradation, concomitant loss of clustered β1 integrins and MT1-MMP from fiber binding sites, and a diffuse cortical distribution of the actin cytoskeleton. Acquisition of protease-independent amoeboid dissemination was confirmed for HT-1080 cells injected into the mouse dermis monitored by intravital multiphoton microscopy. In conclusion, the transition from proteolytic mesenchymal toward nonproteolytic amoeboid movement highlights a supramolecular plasticity mechanism in cell migration and further represents a putative escape mechanism in tumor cell dissemination after abrogation of pericellular proteolysis.

scholarly journals A Role for Fas in Negative Selection of Thymocytes In Vivo

1998 ◽  
Vol 187 (9) ◽  
pp. 1427-1438 ◽  
Author(s):  
Hidehiro Kishimoto ◽  
Charles D. Surh ◽  
Jonathan Sprent
Keyword(s):  
Negative Selection ◽  
Cell Receptor ◽  
Staphylococcal Enterotoxin B ◽  
Thymic Medulla ◽  
Enterotoxin B ◽  
High Doses ◽  
Specific Peptide ◽  
Selection Of

To seek information on the role of Fas in negative selection, we examined subsets of thymocytes from normal neonatal mice versus Fas-deficient lpr/lpr mice injected with graded doses of antigen. In normal mice, injection of 1–100 μg of staphylococcal enterotoxin B (SEB) induced clonal elimination of SEB-reactive Vβ8+ cells at the level of the semi-mature population of HSAhi CD4+ 8− cells found in the thymic medulla; deletion of CD4+ 8+ cells was minimal. SEB injection also caused marked elimination of Vβ8+ HSAhi CD4+ 8− thymocytes in lpr/lpr mice. Paradoxically, however, elimination of these cells in lpr/lpr mice was induced by low-to-moderate doses of SEB (≤1 μg) but not by high doses (100 μg). Similar findings applied when T cell receptor transgenic mice were injected with specific peptide. These findings suggest that clonal elimination of semi-mature medullary T cells is Fas independent at low doses of antigen but Fas dependent at high doses. Previous reports documenting that negative selection is not obviously impaired in lpr/lpr mice could thus reflect that the antigens studied were expressed at only a low level.

“In vivo” amplification of biological activity of tetragastrin by amino acid hydroxamates

1984 ◽  
Vol 4 (12) ◽  
pp. 1009-1015 ◽  
Author(s):  
J. P. Bali ◽  
H. Mattras ◽  
A. Previero ◽  
M. A. Coletti-Previero
Keyword(s):  
Biological Activity ◽  
Amino Acid ◽  
Aromatic Amino Acid ◽  
Aminopeptidase Activity ◽  
Proteolytic Degradation ◽  
Short Peptides ◽  
Rat Blood ◽  
Active Peptides

Rat blood was shown to contain an aminopeptidase which rapidly hydrolyses short peptides containing an aromatic amino acid as N-terminal residue. Using tetragastrin (Trp-Met-Asp-PheNH 2) as substrate, we showed that some amino acid hydroxamates inhibit rat aminopeptidase activity ‘in vitro’ in the following order: HTrpNHOH > HPheNHOH ≫ HAIaNHOH. The same hydroxamates markedly enhanced the biological activity of tetragastrin ‘in vivo’. The amplification of the secretory effect, correlated with the amount of the hydroxamate used, strongly suggests that these compounds can stabilize a number of active peptides in vivo by inhibiting their proteolytic degradation.

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