Expression and function of an even-skipped homolog in the leech Helobdella robusta

Development ◽  
2002 ◽  
Vol 129 (15) ◽  
pp. 3681-3692 ◽  
Author(s):  
Mi Hye Song ◽  
Françoise Z. Huang ◽  
Gwendolen Y. Chang ◽  
David A. Weisblat
Keyword(s):  
Embryonic Stem ◽  
Primary Blast ◽  
Cell Divisions ◽  
Helobdella Robusta ◽  
Pair Rule Gene ◽  
Blast Cells ◽  
And Function ◽  
Pair Rule ◽  
Mitotic Chromatin

We have identified homologs of the Drosophila pair-rule gene even-skipped in the glossiphoniid leeches Helobdella robusta and Theromyzon trizonare. In leech embryos, segments arise sequentially from five pairs of embryonic stem cells (teloblasts) that undergo iterated divisions to generate columns (bandlets) of segmental founder cells (primary blast cells), which in turn generate segmentally iterated sets of definitive progeny. In situ hybridization revealed that Hro-eve is expressed in the teloblasts and primary blast cells, and that these transcripts appear to be associated with mitotic chromatin. In more advanced embryos, Hro-eve is expressed in segmentally iterated sets of cells in the ventral nerve cord. Lineage analysis revealed that neurons expressing Hro-eve arise from the N teloblast. To assess the function of Hro-eve, we examined embryos in which selected blastomeres had been injected with antisense Hro-eve morpholino oligonucleotide (AS-Hro-eve MO), concentrating on the primary neurogenic (N teloblast) lineage. Injection of AS-Hro-eve MO perturbed the normal patterns of teloblast and blast cell divisions and disrupted gangliogenesis. These results suggest that Hro-eve is important in regulating early cell divisions through early segmentation, and that it also plays a role in neuronal differentiation.

Teneurin-1, a vertebrate homologue of the Drosophila pair-rule gene ten-m, is a neuronal protein with a novel type of heparin-binding domain

1999 ◽  
Vol 112 (12) ◽  
pp. 2019-2032 ◽  
Author(s):  
A.D. Minet ◽  
B.P. Rubin ◽  
R.P. Tucker ◽  
S. Baumgartner ◽  
R. Chiquet-Ehrismann
Keyword(s):  
Sequence Motifs ◽  
Heparin Binding ◽  
Terminal Part ◽  
Phylogenetic Conservation ◽  
Neuronal Protein ◽  
Repeat Proteins ◽  
Heparin Binding Domain ◽  
Pair Rule Gene ◽  
Pair Rule

The Drosophila gene ten-m is the first pair-rule gene not encoding a transcription factor, but an extracellular protein. We have characterized a highly conserved chicken homologue that we call teneurin-1. The C-terminal part harbors 26 repetitive sequence motifs termed YD-repeats. The YD-repeats are most similar to the core of the rhs elements of Escherichia coli. Related repeats in toxin A of Clostridium difficile are known to bind specific carbohydrates. We show that recombinantly expressed proteins containing the YD-repeats of teneurin-1 bind to heparin. Furthermore, heparin lyase treatment of extracts of cells expressing recombinant YD-repeat protein releases this protein from high molecular mass aggregates. In situ hybridization and immunostaining reveals teneurin-1 expression in neurons of the developing visual system of chicken and Drosophila. This phylogenetic conservation of neuronal expression from flies to birds implies fundamental roles for teneurin-1 in neurogenesis. This is supported by the neurite outgrowth occurring on substrates made of recombinant YD-repeat proteins, which can be inhibited by heparin. Database searches resulted in the identification of ESTs encoding at least three further members of the teneurin family of proteins. Furthermore, the human teneurin-1 gene could be identified on chromosome Xq24/25, a region implied in an X-linked mental retardation syndrome.

scholarly journals Shifting roles of Drosophila pair-rule gene orthologs: segmental expression and function in the milkweed bug Oncopeltus fasciatus

Development ◽  
2019 ◽  
Vol 146 (17) ◽  
pp. dev181453 ◽  
Author(s):  
Katie Reding ◽  
Mengyao Chen ◽  
Yong Lu ◽  
Alys M. Cheatle Jarvela ◽  
Leslie Pick
Keyword(s):  
Oncopeltus Fasciatus ◽  
Milkweed Bug ◽  
Pair Rule Gene ◽  
And Function ◽  
Gene Orthologs ◽  
Segmental Expression ◽  
Pair Rule

scholarly journals Conservation and variation in pair-rule gene expression and function in the intermediate-germ beetleDermestes maculatus

Development ◽  
2017 ◽  
Vol 144 (24) ◽  
pp. 4625-4636 ◽  
Author(s):  
Jie Xiang ◽  
Katie Reding ◽  
Alison Heffer ◽  
Leslie Pick
Keyword(s):  
Gene Expression ◽  
Pair Rule Gene ◽  
And Function ◽  
Pair Rule

Identification of a neurogenic sublineage required for CNS segmentation in an Annelid

Development ◽  
1995 ◽  
Vol 121 (7) ◽  
pp. 2091-2097 ◽  
Author(s):  
F.A. Ramirez ◽  
C.J. Wedeen ◽  
D.K. Stuart ◽  
D. Lans ◽  
D.A. Weisblat
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Embryonic Stem ◽  
Lineage Tracing ◽  
Posterior Edge ◽  
Primary Blast ◽  
Segment Polarity ◽  
Blast Cells ◽  
Segment Polarity Gene ◽  
Polarity Gene

In embryos of leeches (phylum Annelida), metameric structures arise sequentially from a germinal plate comprising the descendants of five pairs of embryonic stem cells called teloblasts. It has been shown that transverse stripes of cells expressing ht-en (a homolog of engrailed, a Drosophila segment polarity gene), arise in the germinal plate prior to the appearance of segmental ganglia and that, in the main neurogenic lineage (derived from the N teloblasts), the stripe of cells expressing ht-en demarcates the boundary between prospective segmental ganglia. Previous lineage-tracing experiments had suggested that the clones of nf and ns primary blast cells in the N lineage are confined to within segmental borders. This conclusion was called into question by the observation that the cells expressing ht-en do not appear to be at the very posterior edge of the nf clone, from which they arise. To resolve this issue, we have injected individual primary blast cells with fluorescent lineage tracers; we find that cells in the nf clone actually straddle two adjacent ganglia. Moreover, using photoablation techniques, we find that the nf clone is required for proper morphogenesis of the segmentally iterated central nervous system (CNS).

scholarly journals Shifting roles of Drosophila pair-rule gene orthologs: segmental expression and function in the milkweed bug Oncopeltus fasciatus

2019 ◽  
Author(s):  
Katie Reding ◽  
Mengyao Chen ◽  
Yong Lu ◽  
Alys M. Cheatle Jarvela ◽  
Leslie Pick
Keyword(s):  
Oncopeltus Fasciatus ◽  
Regulatory Pathways ◽  
Milkweed Bug ◽  
Regulatory Circuits ◽  
Hemimetabolous Insect ◽  
Pair Rule Gene ◽  
Summary Statement ◽  
And Function ◽  
Gene Orthologs ◽  
Pair Rule

AbstractThe discovery of pair-rule genes (PRGs) in Drosophila revealed the existence of an underlying two-segment-wide prepattern directing embryogenesis. The milkweed bug Oncopeltus, a hemimetabolous insect, is a more representative arthropod: most of its segments form sequentially after gastrulation. Here we report the expression and function of orthologs of the complete set of nine Drosophila PRGs in Oncopeltus. Seven Of-PRG-orthologs are expressed in stripes in the primordia of every segment, rather than every-other segment, Of-runt is PR-like, and several are also expressed in the segment addition zone. RNAi-mediated knockdown of Of-odd-skipped, paired and sloppy-paired impacted all segments, with no indication of PR-like register. We confirm that Of-E75A is expressed in PR-like stripes, although it is not PR in Drosophila, demonstrating the existence of an underlying PR-like prepattern in Oncopeltus. These findings reveal that a switch occurred in regulatory circuits leading to segment formation: while several holometabolous insects are “Drosophila-like,” utilizing PRG-orthologs for PR-patterning, most Of-PRGs are expressed segmentally in Oncopeltus, a more basally-branching insect. Thus, an evolutionarily stable phenotype – segment formation – is directed by alternate regulatory pathways in diverse species.Summary StatementDespite the broad of conservation of segmentation in insects, the regulatory genes underlying this process in Drosophila have different roles in the hemipteran, Oncopeltus fasciatus.

Tissue Factor (TF) and Urokinase Plasminogen Activator Receptor (uPAR) and Bleeding Complications in Leukemic Patients

1997 ◽  
Vol 77 (01) ◽  
pp. 062-070 ◽  
Author(s):  
Chary López-Pedrera ◽  
Merce Jardí ◽  
Maria del Mar Malagón ◽  
Julia Inglés-Esteve ◽  
Gabriel Dorado ◽  
...  
Keyword(s):  
Tissue Factor ◽  
Leukemic Cell ◽  
Bleeding Complications ◽  
Urokinase Plasminogen Activator Receptor ◽  
Leukemic Cell Lines ◽  
Number Of Patients ◽  
Blast Cells ◽  
Plasminogen Activator Receptor ◽  
Hemostatic Disorder

SummaryTissue factor (TF) and urokinase receptor (uPAR) are key cellular receptors triggering, respectively, coagulation and fibrinolysis. Bleeding complications among leukemic patients have been related to an abnormal expression of TF by blast cells and/or to an abnormal fibrinolytic response. In this study the expression of TF and uPAR has been assessed in 18 acute non-lymphoblastic and 8 lymphoblastic leukemic blast cells using several methodological approaches. TF mRNA was evaluated by in situ hybridization and TF and uPAR antigen were evaluated immunologically in cell lysates and on the cell surface by flow cytometry. In addition, TF-procoagulant activity was measured in coagulation-based assays. The reliability of these methods was corroborated in six leukemic cell lines of different lineages and states of maturation. Disseminated intravascular coagulation was detected in two M3 leukemia patients whose blast cells expressed high amounts of TF. Hyperfibrinolysis was detected in one M1 and two M2 patients, whose blast cells displayed a high content of uPAR antigen, but no TF. Furthermore, M5 leukemia blast cells expressed both TF and uPAR, although no hemostatic defects or bleeding complications were detected in these patients. Taken together, although a limited number of patients was included in this study, these data suggest that in leukemia patients exhibiting bleeding, either TF or uPAR are expressed by their blast cells. However, the presence of these receptors does not necessarily imply the existence of a hemostatic disorder.

scholarly journals Network analysis of the left anterior descending coronary arteries in swim-trained rats by an in situ video microscopic technique

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Marianna Török ◽  
Petra Merkely ◽  
Anna Monori-Kiss ◽  
Eszter Mária Horváth ◽  
Réka Eszter Sziva ◽  
...  
Keyword(s):  
Sex Differences ◽  
Left Ventricular ◽  
Resistance Artery ◽  
Frequency Spectra ◽  
Stress Markers ◽  
Lv Mass ◽  
Network Properties ◽  
Exercise Induced ◽  
And Function

Abstract Background We aimed to identify sex differences in the network properties and to recognize the geometric alteration effects of long-term swim training in a rat model of exercise-induced left ventricular (LV) hypertrophy. Methods Thirty-eight Wistar rats were divided into four groups: male sedentary, female sedentary, male exercised and female exercised. After training sessions, LV morphology and function were checked by echocardiography. The geometry of the left coronary artery system was analysed on pressure-perfused, microsurgically prepared resistance artery networks using in situ video microscopy. All segments over > 80 μm in diameter were studied using divided 50-μm-long cylindrical ring units of the networks. Oxidative-nitrative (O-N) stress markers, adenosine A2A and estrogen receptor (ER) were investigated by immunohistochemistry. Results The LV mass index, ejection fraction and fractional shortening significantly increased in exercised animals. We found substantial sex differences in the coronary network in the control groups and in the swim-trained animals. Ring frequency spectra were significantly different between male and female animals in both the sedentary and trained groups. The thickness of the wall was higher in males as a result of training. There were elevations in the populations of 200- and 400-μm vessel units in males; the thinner ones developed farther and the thicker ones closer to the orifice. In females, a new population of 200- to 250-μm vessels appeared unusually close to the orifice. Conclusions Physical activity and LV hypertrophy were accompanied by a remodelling of coronary resistance artery network geometry that was different in both sexes.

scholarly journals Grafts Derived from an α-Synuclein Triplication Patient Mediate Functional Recovery but Develop Disease-Associated Pathology in the 6-OHDA Model of Parkinson’s Disease

2020 ◽  
pp. 1-14
Author(s):  
Shelby Shrigley ◽  
Fredrik Nilsson ◽  
Bengt Mattsson ◽  
Alessandro Fiorenzano ◽  
Janitha Mudannayake ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Cell Lines ◽  
Functional Recovery ◽  
Embryonic Stem ◽  
Hesc Line ◽  
Alternative Source ◽  
And Function

Background: Human induced pluripotent stem cells (hiPSCs) have been proposed as an alternative source for cell replacement therapy for Parkinson’s disease (PD) and they provide the option of using the patient’s own cells. A few studies have investigated transplantation of patient-derived dopaminergic (DA) neurons in preclinical models; however, little is known about the long-term integrity and function of grafts derived from patients with PD. Objective: To assess the viability and function of DA neuron grafts derived from a patient hiPSC line with an α-synuclein gene triplication (AST18), using a clinical grade human embryonic stem cell (hESC) line (RC17) as a reference control. Methods: Cells were differentiated into ventral mesencephalic (VM)-patterned DA progenitors using an established GMP protocol. The progenitors were then either terminally differentiated to mature DA neurons in vitro or transplanted into 6-hydroxydopamine (6-OHDA) lesioned rats and their survival, maturation, function, and propensity to develop α-synuclein related pathology, were assessed in vivo. Results: Both cell lines generated functional neurons with DA properties in vitro. AST18-derived VM progenitor cells survived transplantation and matured into neuron-rich grafts similar to the RC17 cells. After 24 weeks, both cell lines produced DA-rich grafts that mediated full functional recovery; however, pathological changes were only observed in grafts derived from the α-synuclein triplication patient line. Conclusion: This data shows proof-of-principle for survival and functional recovery with familial PD patient-derived cells in the 6-OHDA model of PD. However, signs of slowly developing pathology warrants further investigation before use of autologous grafts in patients.

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