scholarly journals Apyrase (Nucleoside Triphosphate-Diphosphohydrolase) and Extracellular Nucleotides Regulate Cotton Fiber Elongation in Cultured Ovules

2009 ◽  
Vol 152 (2) ◽  
pp. 1073-1083 ◽  
Author(s):  
Greg Clark ◽  
Jonathan Torres ◽  
Scott Finlayson ◽  
Xueying Guan ◽  
Craig Handley ◽  
...  
Keyword(s):  
Cotton Fiber ◽  
Extracellular Nucleotides ◽  
Nucleoside Triphosphate ◽  
Fiber Elongation ◽  
Nucleoside Triphosphate Diphosphohydrolase

scholarly journals Role of Ca2+ in Mediating Plant Responses to Extracellular ATP and ADP

2018 ◽  
Vol 19 (11) ◽  
pp. 3590 ◽  
Author(s):  
Greg Clark ◽  
Stanley Roux
Keyword(s):  
Cytosolic Calcium ◽  
Defense Responses ◽  
Receptor Activation ◽  
Extracellular Atp ◽  
Extracellular Nucleotides ◽  
Nucleoside Triphosphate ◽  
Plant Responses ◽  
Downstream Signaling ◽  
Nucleoside Triphosphate Diphosphohydrolase

Among the most recently discovered chemical regulators of plant growth and development are extracellular nucleotides, especially extracellular ATP (eATP) and extracellular ADP (eADP). Plant cells release ATP into their extracellular matrix under a variety of different circumstances, and this eATP can then function as an agonist that binds to a specific receptor and induces signaling changes, the earliest of which is an increase in the concentration of cytosolic calcium ([Ca2+]cyt). This initial change is then amplified into downstream-signaling changes that include increased levels of reactive oxygen species and nitric oxide, which ultimately lead to major changes in the growth rate, defense responses, and leaf stomatal apertures of plants. This review presents and discusses the evidence that links receptor activation to increased [Ca2+]cyt and, ultimately, to growth and diverse adaptive changes in plant development. It also discusses the evidence that increased [Ca2+]cyt also enhances the activity of apyrase (nucleoside triphosphate diphosphohydrolase) enzymes that function in multiple subcellular locales to hydrolyze ATP and ADP, and thus limit or terminate the effects of these potent regulators.

scholarly journals Expression of P2Y nucleotide receptors and ectonucleotidases in quiescent and activated rat hepatic stellate cells

2004 ◽  
Vol 287 (2) ◽  
pp. G417-G424 ◽  
Author(s):  
Jonathan A. Dranoff ◽  
Mika Ogawa ◽  
Emma A. Kruglov ◽  
Marianna D. A. Gaça ◽  
Jean Sévigny ◽  
...  
Keyword(s):  
Mrna Expression ◽  
Hepatic Stellate Cells ◽  
Stellate Cells ◽  
P2y Receptors ◽  
Extracellular Nucleotides ◽  
Nucleoside Triphosphate ◽  
P2y Receptor ◽  
Rt Pcr ◽  
Nucleoside Triphosphate Diphosphohydrolase ◽  
Receptor Inhibitor

Extracellular nucleotides regulate a variety of cellular activities, including proliferation of fibrogenic cells outside of the liver. However, the expression of receptors for extracellular nucleotides in hepatic stellate cells (HSC) is unknown. Thus our aims were to investigate the expression of mediators of nucleotide signaling in HSC and to determine whether extracellular nucleotides regulate HSC function. Confocal video microscopy was used to observe nucleotide-induced changes in cytosolic Ca2+ (Cai2+) in live HSC. P2Y receptor subtype expression and ectonucleotidase expression in quiescent and activated HSC were determined using RT-PCR, Northern blot, immunoblot, and confocal immunofluorescence. Functional ectonucleotidase activity was assessed using a colorimetric method. Nucleotide-sensitive procollagen-1 mRNA expression in activated HSC was assessed using real-time RT-PCR. Extracellular ATP increased Cai2+ in HSC; this was inhibited by the P2 receptor inhibitor suramin. Quiescent HSC expressed the P2Y subtypes P2Y2 and P2Y4 and were activated by ATP and UTP, whereas activated HSC expressed the P2Y subtype P2Y6 and were activated by UDP and ATP. Activated but not quiescent HSC expressed the ectonucleotidase nucleoside triphosphate diphosphohydrolase 2, extracellular UDP tripled procollagen-1 mRNA expression in activated HSC, and this was inhibited by the P2Y receptor inhibitor suramin. HSC express functional P2Y receptors and switch the expression of P2Y receptor subtypes on activation. Moreover, HSC differentially regulate nucleoside triphosphate diphosphohydrolase expression after activation. Because activation of P2Y receptors in activated HSC regulates procollagen-1 transcription, P2Y receptors may be an attractive target to prevent or treat liver fibrosis.

Differential catalytic properties and vascular topography of murine nucleoside triphosphate diphosphohydrolase 1 (NTPDase1) and NTPDase2 have implications for thromboregulation

Blood ◽  
2002 ◽  
Vol 99 (8) ◽  
pp. 2801-2809 ◽  
Author(s):  
Jean Sévigny ◽  
Christian Sundberg ◽  
Norbert Braun ◽  
Olaf Guckelberger ◽  
Eva Csizmadia ◽  
...  
Keyword(s):  
Platelet Aggregation ◽  
Adenosine Monophosphate ◽  
Adenosine Diphosphate ◽  
Receptor Activation ◽  
Extracellular Nucleotides ◽  
Nucleoside Triphosphate ◽  
Uridine Diphosphate ◽  
P2 Receptor ◽  
Nucleoside Triphosphate Diphosphohydrolase ◽  
Vessel Injury

Abstract Nucleoside triphosphate diphosphohydrolases (NTPDases) are a recently described family of ectonucleotidases that differentially hydrolyze the γ and β phosphate residues of extracellular nucleotides. Expression of this enzymatic activity has the potential to influence nucleotide P2 receptor signaling within the vasculature. We and others have documented that NTPDase1 (CD39, 78 kd) hydrolyzes both triphosphonucleosides and diphosphonucleosides and thereby terminates platelet aggregation responses to adenosine diphosphate (ADP). In contrast, we now show that NTPDase2 (CD39L1, 75 kd), a preferential nucleoside triphosphatase, activates platelet aggregation by converting adenosine triphosphate (ATP) to ADP, the specific agonist of P2Y1 and P2Y12 receptors. We developed specific antibodies to murine NTPDase1 and NTPDase2 and observed that both enzymes are present in the cardiac vasculature; NTPDase1 is expressed by endothelium, endocardium, and to a lesser extent by vascular smooth muscle, while NTPDase2 is associated with the adventitia of muscularized vessels, microvascular pericytes, and other cell populations in the subendocardial space. Moreover, NTPDase2 represents a novel marker for microvascular pericytes. Differential expression of NTPDases in the vasculature suggests spatial regulation of nucleotide-mediated signaling. In this context, NTPDase1 should abrogate platelet aggregation and recruitment in intact vessels by the conversion of ADP to adenosine monophosphate, while NTPDase2 expression would promote platelet microthrombus formation at sites of extravasation following vessel injury. Our data suggest that specific NTPDases, in tandem with ecto-5′-nucleotidase, not only terminate P2 receptor activation and trigger adenosine receptors but may also allow preferential activation of specific subsets of P2 receptors sensitive to ADP (eg, P2Y1, P2Y3, P2Y12) and uridine diphosphate (P2Y6).

scholarly journals Cloning, purification, and identification of the liver canalicular ecto-ATPase as NTPDase8

2007 ◽  
Vol 292 (3) ◽  
pp. G785-G795 ◽  
Author(s):  
Michel Fausther ◽  
Joanna Lecka ◽  
Filip Kukulski ◽  
Sébastien A. Lévesque ◽  
Julie Pelletier ◽  
...  
Keyword(s):  
Rat Liver ◽  
Bile Secretion ◽  
Amino Acid Sequences ◽  
Extracellular Nucleotides ◽  
Nucleoside Triphosphate ◽  
Transmembrane Receptors ◽  
Downstream Signaling ◽  
Nucleoside Triphosphate Diphosphohydrolase ◽  
Nucleoside Salvage ◽  
Triton X

Extracellular nucleotides regulate critical liver functions via the activation of specific transmembrane receptors. The hepatic levels of extracellular nucleotides, and therefore the related downstream signaling cascades, are modulated by cell-surface enzymes called ectonucleotidases, including nucleoside triphosphate diphosphohydrolase-1 (NTPDase1/CD39), NTPDase2/CD39L1, and ecto-5′-nucleotidase/CD73. The goal of this study was to determine the molecular identity of the canalicular ecto-ATPase/ATPDase that we hypothesized to correspond to the recently cloned NTPDase8. Human and rat NTPDase8 cDNAs were cloned, and the genes were located on chromosome loci 9q34 and 3p13, respectively. The recombinant proteins, expressed in COS-7 and HEK293T cells, were biochemically characterized. NTPDase8 was also purified from rat liver by Triton X-100 solubilization, followed by DEAE, Affigel Blue, and concanavalin A chromatographies. Importantly, NTPDase8 was responsible for the major ectonucleotidase activity in liver. The ion requirement, apparent Km values, nucleotide hydrolysis profile, and preference as well as the resistance to azide were similar for recombinant NTPDase8s and both purified rat NTPDase8 and porcine canalicular ecto-ATPase/ATPDase. The partial NH2-terminal amino acid sequences of all NTPDase8s share high identity with the purified liver canalicular ecto-ATPase/ATPDase. Histochemical analysis showed high ectonucleotidase activities in bile canaliculi and large blood vessels of rat liver, in agreement with the immunolocalization of NTPDase1, 2, and 8 with antibodies developed for this study. No NTPDase3 expression could be detected in liver. In conclusion, NTPDase8 is the canalicular ecto-ATPase/ATPDase and is responsible for the main hepatic NTPDase activity. The canalicular localization of this enzyme suggests its involvement in the regulation of bile secretion and/or nucleoside salvage.

scholarly journals NTPDase1 Modulates Smooth Muscle Contraction in Mice Bladder by Regulating Nucleotide Receptor Activation Distinctly in Male and Female

Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 147
Author(s):  
Romuald Brice Babou Kammoe ◽  
Gilles Kauffenstein ◽  
Julie Pelletier ◽  
Bernard Robaye ◽  
Jean Sévigny
Keyword(s):  
Smooth Muscle ◽  
Ex Vivo ◽  
Smooth Muscle Contraction ◽  
Receptor Activation ◽  
Nucleoside Triphosphate ◽  
Nucleotide Receptors ◽  
Nerve Terminals ◽  
Wild Type ◽  
Nucleoside Triphosphate Diphosphohydrolase ◽  
Bladder Contraction

Nucleotides released by smooth muscle cells (SMCs) and by innervating nerve terminals activate specific P2 receptors and modulate bladder contraction. We hypothesized that cell surface enzymes regulate SMC contraction in mice bladder by controlling the concentration of nucleotides. We showed by immunohistochemistry, enzymatic histochemistry, and biochemical activities that nucleoside triphosphate diphosphohydrolase-1 (NTPDase1) and ecto-5′-nucleotidase were the major ectonucleotidases expressed by SMCs in the bladder. RT-qPCR revealed that, among the nucleotide receptors, there was higher expression of P2X1, P2Y1, and P2Y6 receptors. Ex vivo, nucleotides induced a more potent contraction of bladder strips isolated from NTPDase1 deficient (Entpd1−/−) mice compared to wild type controls. The strongest responses were obtained with uridine 5′-triphosphate (UTP) and uridine 5′-diphosphate (UDP), suggesting the involvement of P2Y6 receptors, which was confirmed with P2ry6−/− bladder strips. Interestingly, this response was reduced in female bladders. Our results also suggest the participation of P2X1, P2Y2 and/or P2Y4, and P2Y12 in these contractions. A reduced response to the thromboxane analogue U46619 was also observed in wild type, Entpd1−/−, and P2ry6−/− female bladders showing another difference due to sex. In summary, NTPDase1 modulates the activation of nucleotide receptors in mouse bladder SMCs, and contractions induced by P2Y6 receptor activation were weaker in female bladders.

scholarly journals GhPIPLC2D promotes cotton fiber elongation by enhancing ethylene biosynthesis

iScience ◽  
2021 ◽  
Vol 24 (7) ◽  
pp. 102737
Author(s):  
Liping Zhu ◽  
Lingling Dou ◽  
Haihong Shang ◽  
Hongbin Li ◽  
Jianing Yu ◽  
...  
Keyword(s):  
Cotton Fiber ◽  
Ethylene Biosynthesis ◽  
Fiber Elongation

scholarly journals GhPIPLC2D promotes cotton fiber elongation by enhancing ethylene biosynthesis

iScience ◽  
2021 ◽  
pp. 102199
Author(s):  
Liping Zhu ◽  
Lingling Dou ◽  
Haihong Shang ◽  
Hongbin Li ◽  
Jianing Yu ◽  
...  
Keyword(s):  
Cotton Fiber ◽  
Ethylene Biosynthesis ◽  
Fiber Elongation

scholarly journals Cotton fiber elongation requires the transcription factor Gh MYB 212 to regulate sucrose transportation into expanding fibers

2019 ◽  
Vol 222 (2) ◽  
pp. 864-881 ◽  
Author(s):  
Wenjie Sun ◽  
Zhengyin Gao ◽  
Jun Wang ◽  
Yiqun Huang ◽  
Yun Chen ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Cotton Fiber ◽  
Fiber Elongation

Exogenous Jasmonic Acid Inhibits Cotton Fiber Elongation

2012 ◽  
Vol 31 (4) ◽  
pp. 599-605 ◽  
Author(s):  
Jiafu Tan ◽  
Lili Tu ◽  
Fenglin Deng ◽  
Rui Wu ◽  
Xianlong Zhang
Keyword(s):  
Jasmonic Acid ◽  
Cotton Fiber ◽  
Fiber Elongation
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