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NCBI: db=pubmed; Term=(((((((((echinoderm) AND developmental biology) OR strongylocentrotus purpuratus) OR patiria miniata) OR lytechinus variegatus) OR eucidaris tribuloides) OR parastichopus parvimensis) OR ophiothrix apiculata) OR allocentrotus fragilis) OR strongylocentrotus franciscanus AND ( ( Humans[Mesh] OR Animals[Mesh:noexp] ) ) AND ("last 5 years"[PDat])
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The diversity of nanos expression in echinoderm embryos supports different mechanisms in germ cell specification.

Wed, 04/26/2017 - 20:39
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The diversity of nanos expression in echinoderm embryos supports different mechanisms in germ cell specification.

Evol Dev. 2016 Jul;18(4):267-78

Authors: Fresques T, Swartz SZ, Juliano C, Morino Y, Kikuchi M, Akasaka K, Wada H, Yajima M, Wessel GM

Abstract
Specification of the germ cell lineage is required for sexual reproduction in all animals. However, the timing and mechanisms of germ cell specification is remarkably diverse in animal development. Echinoderms, such as sea urchins and sea stars, are excellent model systems to study the molecular and cellular mechanisms that contribute to germ cell specification. In several echinoderm embryos tested, the germ cell factor Vasa accumulates broadly during early development and is restricted after gastrulation to cells that contribute to the germ cell lineage. In the sea urchin, however, the germ cell factor Vasa is restricted to a specific lineage by the 32-cell stage. We therefore hypothesized that the germ cell specification program in the sea urchin/Euechinoid lineage has evolved to an earlier developmental time point. To test this hypothesis we determined the expression pattern of a second germ cell factor, Nanos, in four out of five extant echinoderm clades. Here we find that Nanos mRNA does not accumulate until the blastula stage or later during the development of all other echinoderm embryos except those that belong to the Echinoid lineage. Instead, Nanos is expressed in a restricted domain at the 32-128 cell stage in Echinoid embryos. Our results support the model that the germ cell specification program underwent a heterochronic shift in the Echinoid lineage. A comparison of Echinoid and non-Echinoid germ cell specification mechanisms will contribute to our understanding of how these mechanisms have changed during animal evolution.

PMID: 27402572 [PubMed - indexed for MEDLINE]

Categories: pubmed

Synthesis and anti-mitotic activity of 6,7-dihydro-4H-isothiazolo[4,5-b]pyridin-5-ones: In vivo and cell-based studies.

Thu, 04/13/2017 - 20:06
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Synthesis and anti-mitotic activity of 6,7-dihydro-4H-isothiazolo[4,5-b]pyridin-5-ones: In vivo and cell-based studies.

Eur J Med Chem. 2017 Jan 05;125:573-585

Authors: Semenov VV, Lichitsky BV, Komogortsev AN, Dudinov AA, Krayushkin MM, Konyushkin LD, Atamanenko OP, Karmanova IB, Strelenko YA, Shor B, Semenova MN, Kiselyov AS

Abstract
A series of 3,7-diaryl-6,7-dihydroisothiazolo [4,5-b]pyridin-5(4H)-ones 8 and 9 was synthesized by multicomponent condensation of 3-aryl-5-isothiazolecarboxylic acid esters 4a-f with aromatic (or thienyl) aldehydes 7 and Meldrum's acid in an acidic medium. The targeted compounds were evaluated for their antimitotic microtubule destabilizing activity using in vivo phenotypic sea urchin embryo model and in vitro human cancer cell-based assays. Selected dihydroisothiazolopyridinones altered sea urchin egg cleavage in 2-10 nM concentrations together with significant cytotoxicity against cancer cells including chemoresistant cell lines (IC50 in submicromolar - low nanomolar concentration range). Both approaches confirmed antimitotic microtubule destabilizing mechanism of action of the izothiazole derivatives. Structure-activity relationship study determined the importance of p-methoxybenzene A-ring for the antiproliferative effect. The most potent compound 9b containing p-methoxybenzene A-ring and thiophene B-ring caused mitotic arrest and disintegration of cell microtubules.

PMID: 27718473 [PubMed - indexed for MEDLINE]

Categories: pubmed

A novel MKK gene (AjMKK3/6) in the sea cucumber Apostichopus japonicus: Identification, characterization and its response to pathogenic challenge.

Tue, 04/11/2017 - 20:06
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A novel MKK gene (AjMKK3/6) in the sea cucumber Apostichopus japonicus: Identification, characterization and its response to pathogenic challenge.

Fish Shellfish Immunol. 2017 Feb;61:24-33

Authors: Wang Y, Chen G, Li K, Sun J, Song J, Zhan Y, Zhang X, Yang L, Chang Y

Abstract
The mitogen-activated protein kinase kinases (MKKs) are key components of MAP kinase (MAPK) cascades and function as redox-regulated signaling factors in pathological and physiological processes. In this study, we identified a novel MKK3/6 gene in the sea cucumber Apostichopus japonicus (designated as AjMKK3/6) by transcriptome database mining and rapid amplification of cDNA ends (RACE) approaches. Sequence analysis and protein structure prediction showed that AjMKK3/6 is highly conserved as compared to those from other invertebrate and vertebrate species. Molecular phylogeny result revealed that AjMKK3/6 exhibited a closest relationship with that from Strongylocentrotus purpuratus. Quantitative real-time PCR was employed to determine the expression profiles of AjMKK3/6 in healthy adult A. japonicus tissues and in coelomocytes after Vibrio splendidus infection in vivo, respectively. As results shown, AjMKK3/6 was ubiquitously expressed in all examined tissues of healthy adult A. japonicus with a relative expression level from high to low as body wall > tube feet > coelomocytes > respiratory tree > intestine > longitudinal muscle. Significant expression changes of AjMKK3/6 in coelomocytes were observed at 12 h- and 72 h-after V. splendidus infection, respectively. In general, the current study will enrich our knowledge of characterizations and immno-functions of MKK3/6 in sea cucumbers.

PMID: 27988308 [PubMed - indexed for MEDLINE]

Categories: pubmed

Involvement of l(-)-rhamnose in sea urchin gastrulation. Part II: α-l-Rhamnosidase.

Tue, 04/11/2017 - 20:06
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Involvement of l(-)-rhamnose in sea urchin gastrulation. Part II: α-l-Rhamnosidase.

Zygote. 2016 Jun;24(3):371-7

Authors: Liang J, Aleksanyan H, Metzenberg S, Oppenheimer SB

Abstract
The sea urchin embryo is recognized as a model system to reveal developmental mechanisms involved in human health and disease. In Part I of this series, six carbohydrates were tested for their effects on gastrulation in embryos of the sea urchin Lytechinus pictus. Only l-rhamnose caused dramatic increases in the numbers of unattached archenterons and exogastrulated archenterons in living, swimming embryos. It was found that at 30 h post-fertilization the l-rhamnose had an unusual inverse dose-dependent effect, with low concentrations (1-3 mM) interfering with development and higher concentrations (30 mM) having little to no effect on normal development. In this study, embryos were examined for inhibition of archenteron development after treatment with α-l-rhamnosidase, an endoglycosidase that removes terminal l-rhamnose sugars from glycans. It was observed that the enzyme had profound effects on gastrulation, an effect that could be suppressed by addition of l-rhamnose as a competitive inhibitor. The involvement of l-rhamnose-containing glycans in sea urchin gastrulation was unexpected, since there are no characterized biosynthetic pathways for rhamnose utilization in animals. It is possible there exists a novel l-rhamnose-containing glycan in sea urchins, or that the enzyme and sugar interfere with the function of rhamnose-binding lectins, which are components of the innate immune system in many vertebrate and invertebrate species.

PMID: 26168775 [PubMed - indexed for MEDLINE]

Categories: pubmed

Characterization and expression analysis of a thioredoxin-like protein gene in the sea cucumber Apostichopus japonicus.

Thu, 03/23/2017 - 19:20
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Characterization and expression analysis of a thioredoxin-like protein gene in the sea cucumber Apostichopus japonicus.

Fish Shellfish Immunol. 2016 Nov;58:165-173

Authors: Cheng S, Li C, Wang Y, Yang L, Chang Y

Abstract
As the most important disulfide bond reducates of intracellular oxidordeuctase, thioredoxin (TRX) plays a crucial role in maintaining reducing state of intracellular proteins to normally perform their function. In this study, a cDNA of TRX-like protein gene from Apostichopus japonicus (denoted as AjTRX) was cloned and characterized. The full-length cDNA of AjTRXwas of 1870 bp, consisting of a 5'-UTR of 101 bp, a long 3'-UTR of 887 bp and a 882 bp open reading frame (ORF) encoding a 293 amino acids. The predicted molecular mass and the theoretical PI of the deduced amino acids of AjTRX were 32.3 kDa and 5.52, respectively. Phylogenetic trees showed that AjTRX had a closer evolution relationship with TRX from Strongylocentrotus purpuratus. AjTRX was found to be ubiquitously expressed in all examined tissues including longitudinal muscle, coelomocytes, tube feet, intestine, respiratory tree and body wall indicating a general role in physiological processes. Temporal expression pattern of AjTRX in coelomocytes showed that AjTRX reached two peak expression levels at 8 h and 48 h after Vibrio splendidus challenge with a 8.6 and 9.3-fold increase compared to their control groups, respectively. The recombinant AjTRX protein (rAjTRX) displayed obvious antioxidant activity in a dose-dependent manner, and the higher reducing activity was detected in 20 μM experimental group. All these results strongly suggested that AjTRX could play an important role as an antioxidant in a physiological context, and might be involved in the process of bacterial challenge.

PMID: 27640155 [PubMed - indexed for MEDLINE]

Categories: pubmed