GROWTH AND DEVELOPMENT OF THE MALE GAMETOPHYTE OF GINKGO BILOBA WITHIN THE OVULE (IN VIVO)

Recently, overwhelming evidence has proven that hydrogen sulfide (H2S), which was identified as a gasotransmitter in animals, plays important roles in diverse physiological processes in plants as well. With the discovery and systematic classification of the enzymes producing H2Sin vivo, a better understanding of the mechanisms by which H2S influences plant responses to various stimuli was reached. There are many functions of H2S, including the modulation of defense responses and plant growth and development, as well as the regulation of senescence and maturation. Additionally, mounting evidence indicates that H2S signaling interacts with plant hormones, hydrogen peroxide, nitric oxide, carbon monoxide, and other molecules in signaling pathways.

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Transcriptomic analysis reveals a role for the nervous system in regulating growth and development of Fasciola hepatica juveniles

10.1101/2022.01.13.476286 ◽

2022 ◽

Author(s):

Emily Robb ◽

Erin McCammick ◽

Duncan Wells ◽

Paul McVeigh ◽

Erica Gardiner ◽

...

Keyword(s):

Nervous System ◽

Rapid Growth ◽

Growth And Development ◽

Liver Fluke ◽

Fasciola Hepatica ◽

Expression Profiles ◽

Neuronal Signalling ◽

Growth Development

Fasciola spp. liver fluke have significant impacts in veterinary and human medicine. The absence of a vaccine and increasing anthelmintic resistance threaten sustainable control and underscore the need for novel flukicides. Functional genomic approaches underpinned by in vitro culture of juvenile Fasciola hepatica facilitate control target validation in the most pathogenic life stage. Comparative transcriptomics of in vitro and in vivo maintained 21 day old F. hepatica finds that 86% of genes are expressed at similar levels across maintenance treatments suggesting commonality in core biological functioning within these juveniles. Phenotypic comparisons revealed higher cell proliferation and growth rates in the in vivo juveniles compared to their in vitro counterparts. These phenotypic differences were consistent with the upregulation of neoblast-like stem cell and cell-cycle associated genes in in vivo maintained worms. The more rapid growth/development of in vivo juveniles was further evidenced by a switch in cathepsin protease expression profiles, dominated by cathepsin B in in vitro juveniles and then by cathepsin L in in vivo juveniles. Coincident with more rapid growth/development was the marked downregulation of both classical and peptidergic neuronal signalling components in in vivo maintained juveniles, supporting a role for the nervous system in regulating liver fluke growth and development. Differences in the miRNA complements of in vivo and in vitro juveniles identified 31 differentially expressed miRNAs, notably fhe-let-7a-5p , fhe-mir-124-3p and, miRNAs predicted to target Wnt-signalling, supporting a key role for miRNAs in driving the growth/developmental differences in the in vitro and in vivo maintained juvenile liver fluke. Widespread differences in the expression of neuronal genes in juvenile fluke grown in vitro and in vivo expose significant interplay between neuronal signalling and the rate of growth/development, encouraging consideration of neuronal targets in efforts to dysregulate growth/development for parasite control.

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Chronic exposure to retroviral vector encoded MGDF (mpl-ligand) induces lineage-specific growth and differentiation of megakaryocytes in mice

Blood ◽

10.1182/blood.v86.11.4025.bloodjournal86114025 ◽

1995 ◽

Vol 86 (11) ◽

pp. 4025-4033 ◽

Cited By ~ 109

Author(s):

XQ Yan ◽

D Lacey ◽

F Fletcher ◽

C Hartley ◽

P McElroy ◽

...

Keyword(s):

Growth And Development ◽

Chronic Exposure ◽

Specific Growth ◽

Extramedullary Hematopoiesis ◽

Retroviral Vector ◽

Platelet Recovery ◽

Development Factor ◽

Systematic Effects ◽

Baseline Levels

Megakaryocyte growth and development factor (MGDF) has recently been identified as a ligand for the c-mpl receptor. Using retroviral- mediated gene transfer, MGDF has been overexpressed in mice to evaluate the systematic effects due to chronic exposure to this growth factor. MGDF overexpressing mice had more rapid platelet recovery than control mice after transplantation. Following this recovery, the platelet levels continued increasing to fourfold to eightfold above normal baseline levels and remained elevated (five-fold above control mice) in these animals, which are alive and well at more than 4 months posttransplantation. Increased megakaryocyte numbers were detected in a number of organs in these mice including bone marrow, spleen, liver, and lymph nodes. Prolonged overexpression of MGDF led to decreased marrow hematopoiesis, especially erythropoiesis, with a shift to extramedullary hematopoiesis in the spleen and liver. All the MGDF overexpressing mice analyzed to date developed myelofibrosis and osteosclerosis, possibly induced by megakaryocyte and platelet produced cytokines. No significant effect on other hematopoietic lineages was seen in the MGDF overexpressing mice, showing that the stimulatory effect of MGDF in vivo is restricted to the megakaryocyte lineage.

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Increased Expression of CCN2 in the Red Flashing Light-Induced Myopia in Guinea Pigs

BioMed Research International ◽

10.1155/2013/761823 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Hong Wang ◽

Kang Zhuang ◽

Lei Gao ◽

Linna Zhang ◽

Hongling Yang

Keyword(s):

Gene Expression ◽

Animal Model ◽

Axial Length ◽

Growth And Development ◽

Visual Environment ◽

Biological Processes ◽

Cellular Functions ◽

Ocular Growth ◽

Flashing Light

Visual environment plays an important role in the occurrence of myopia. We previously showed that the different flashing lights could result in distinct effects on the ocular growth and development of myopia. CCN2 has been reported to regulate various cellular functions and biological processes. However, whether CCN2 signaling was involved in the red flashing light-induced myopia still remains unknown. In the present study, we investigated the effects of the red flashing lights exposure on the refraction and axial length of the eyesin vivoand then evaluated their effects on the expression of CCN2 and TGF-βin sclera tissues. Our data showed that the eyes exposed to the red flashing light became more myopic with a significant increase of the axial length and decrease of the refraction. Both CCN2 and TGF-β, as well as p38 MAPK and PI3K, were highly expressed in the sclera tissues exposed to the red flashing light. Both CCN2 and TGF-βwere found to have the same gene expression profilein vivo. In conclusion, our findings found that CCN2 signaling pathway plays an important role in the red flashing light-induced myopiain vivo. Moreover, our study establishes a useful animal model for experimental myopia research.

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Recombinant human megakaryocyte growth and development factor stimulates thrombocytopoiesis in normal nonhuman primates

Blood ◽

10.1182/blood.v86.1.54.bloodjournal86154 ◽

1995 ◽

Vol 86 (1) ◽

pp. 54-59 ◽

Cited By ~ 145

Author(s):

AM Farese ◽

P Hunt ◽

T Boone ◽

TJ MacVittie

Keyword(s):

Bone Marrow ◽

Peripheral Blood ◽

Growth And Development ◽

Nonhuman Primates ◽

Normal Male ◽

Platelet Counts ◽

Development Factor ◽

Development In Vitro

Megakaryocyte growth and development factor (MGDF) is a novel cytokine that binds to the c-mpl receptor and stimulates megakaryocyte development in vitro and in vivo. This report describes the ability of recombinant human (r-Hu) MGDF to affect megakaryocytopoiesis in normal nonhuman primates. r-HuMGDF was administered subcutaneously to normal, male rhesus monkeys once per day for 10 consecutive days at dosages of 2.5, 25, or 250 micrograms/kg of body weight. Bone marrow and peripheral blood were assayed for clonogenic activity and peripheral blood counts were monitored. Circulating platelet counts increased significantly (P < .05) for all doses within 6 days of r-HuMGDF administration and reached maximal levels between day 12 and day 14 postcytokine administration. The 2.5, 25.0, and 250.0 micrograms/kg/d doses elicited peak mean platelet counts that were 592%, 670%, and 449% of baseline, respectively. Bone marrow-derived clonogenic data showed significant increases in the concentration of megakaryocyte (MEG)- colony-forming unit (CFU) and granulocyte-erythroid-macrophage- megakaryocyte (GEMM)-CFU, whereas that of granulocyte-macrophage (GM)- CFU and burst-forming unit-erythroid (BFU-e) remained unchanged during the administration of r-HuMGDF. These data show that r-HuMGDF is a potent stimulator of thrombocytopoiesis in the normal nonhuman primate.

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Platelets Exposed to Elevated Levels of Endogenous Thrombopoietin In Vivo Have a Reduced Response to Megakaryocyte Growth and Development Factor In Vitro

Thrombosis and Haemostasis ◽

10.1055/s-0037-1612918 ◽

2001 ◽

Vol 85 (01) ◽

pp. 152-159 ◽

Cited By ~ 5

Author(s):

Uichi Nishiyama ◽

Haruhiko Morita ◽

Yoshifumi Torii ◽

Tomoaki Kuwaki ◽

Eiko Shimizu ◽

...

Keyword(s):

Growth And Development ◽

Platelet Reactivity ◽

Biochemical Properties ◽

Human Platelets ◽

Janus Kinase ◽

Intravenous Injections ◽

Development Factor ◽

Lower Reactivity

SummaryThrombopoietin (TPO), or megakaryocyte growth and development factor (MGDF), has been shown to potentiate the sensitivity of normal human platelets to various agonists in vitro. The present study investigated the functional and biochemical properties of platelets from mice rendered thrombocytopenic by sublethal irradiation with regard to the reactivity to recombinant murine MGDF (rmMGDF) in vitro. During the course of reversible thrombocytopenia following irradiation, platelets from irradiated mice which had lower platelet counts and reciprocally higher plasma TPO levels showed lower reactivity to rmMGDF in agonist-induced platelet aggregation. Intravenous injections of recombinant soluble murine c-Mpl (sMpl), which has the ability to capture TPO, after irradiation restored the reactivity of platelets at the platelet nadir to rmMGDF. On the other hand, platelets prepared from normal mice 3 h after a single intravenous injection of pegylated rmMGDF did not respond to rmMGDF. There was a marked decrease in c-Mpl and Janus kinase 2 (JAK2) in platelets from irradiated mice at the platelet nadir. Similar results were observed with platelets from mice administered pegylated rmMGDF. JAK2 was only moderately decreased, however, in platelets from mice given sMpl after irradiation. These results indicate that exposure of platelets to increased endogenous TPO levels in vivo in thrombocytopenic mice leads to a reduction in the platelet reactivity to rmMGDF in vitro. Further, these results suggest that the c-Mpl-mediated signaling pathway, which is essential for the priming effect of rmMGDF, is defective in thrombocytopenic murine platelets.

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