Dietary assimilation of a polychlorinated biphenyl in adult sea urchins (Lytechinus pictus) and maternal transfer to their offspring

2000 ◽  
Vol 19 (7) ◽  
pp. 1919-1924 ◽  
Author(s):  
Linda E. Schweitzer ◽  
Steven M. Bay ◽  
I. H.(Mel) Suffet
Keyword(s):  
Polychlorinated Biphenyl ◽  
Sea Urchins ◽  
Maternal Transfer ◽  
Lytechinus Pictus

Toxic effects of polychlorinated biphenyl bio accumulation in sea urchins exposed to contaminated sediments

2003 ◽  
Vol 22 (5) ◽  
pp. 1065-1074
Author(s):  
Eddy Y. Zeng ◽  
Steven M. Bay ◽  
Darrin Greenstein ◽  
Cherrie Vista ◽  
Charlie Yu ◽  
...  
Keyword(s):  
Polychlorinated Biphenyl ◽  
Sea Urchins ◽  
Contaminated Sediments ◽  
Toxic Effects

scholarly journals Organization and evolution of the actin gene family in sea urchins.

1983 ◽  
Vol 3 (10) ◽  
pp. 1824-1833 ◽  
Author(s):  
P J Johnson ◽  
D R Foran ◽  
G P Moore
Keyword(s):  
Sea Urchin ◽  
Sequence Homology ◽  
Copy Number ◽  
Sea Urchins ◽  
Intron Position ◽  
Actin Gene ◽  
Genomic Libraries ◽  
Lytechinus Pictus ◽  
Transcriptional Orientation ◽  
Actin Genes

Genomic libraries of the sea urchins Strongylocentrotus franciscanus and Lytechinus pictus were screened with an actin cDNA clone from Strongylocentrotus purpuratus. Four nonoverlapping clones were isolated and characterized from the S. franciscanus library; three were isolated and characterized from the L. pictus library. Linked genes having the same transcriptional orientation were found on all S. franciscanus clones. Three clones contained two actin genes each; the other clone contained three. In contrast, the L. pictus clones contained only one actin gene. Comparison of actin genomic clones from these three species indicated a difference in the genomic organization of sea urchin actin genes in that the genes appear to be more highly clustered in S. franciscanus than in S. purpuratus and L. pictus. Genomic dot blots and reassociation kinetics demonstrated that the copy number of actin genes in all three species is 15 to 20. Nucleotide sequence homology of actin genes within and among the species was measured by thermal elution. These experiments indicated that there is a high degree of interspecies actin gene sequence homology but that, within each species, actin gene sequences may differ by as much as 30%. Sequencing of two S. franciscanus actin genes revealed introns at the same amino acid positions, 121 and 204, reported for S. purpuratus actin genes. These data demonstrated that the genomic copy number, the transcriptional orientation of linked genes, and, to the extent studied, the intron position of actin genes have evolved similarly in these three species. In contrast, significant change has occurred in the chromosomal arrangement of sea urchin actin genes.

Ectoderm nuclei from sea urchin embryos contain a Spec-DNA binding protein similar to the vertebrate transcription factor USF

Development ◽  
1990 ◽  
Vol 110 (1) ◽  
pp. 259-272 ◽  
Author(s):  
C.R. Tomlinson ◽  
M.T. Kozlowski ◽  
W.H. Klein
Keyword(s):  
Transcription Factor ◽  
Sea Urchin ◽  
Sea Urchins ◽  
Dna Interaction ◽  
Initiation Site ◽  
Upstream Stimulatory Factor ◽  
Transcriptional Initiation ◽  
Lytechinus Pictus ◽  
Conserved Sequence ◽  
A Cell

The Spec gene family of Stronglyocentrotus purpuratus is expressed exclusively in aboral ectoderm cells during embryogenesis. To investigate the regulation of Spec gene activity, the region around the Spec1 transcriptional initiation site was analyzed for sites of protein-DNA interaction. One high-affinity site bound a factor termed SpF1 within the Spec1 5′ untranslated leader region at position +39 to +60. The core sequence recognized by SpF1, CACGTG, is the same as that of the upstream stimulatory factor (USF), a widely occurring vertebrate transcription factor containing a myc-HLH motif. A comparison of USF- and SpF1-binding activities suggested that SpF1 was a sea urchin version of USF. SpF1 activity was detectable only in ectoderm cells of the embryo, implying that it has a role as a cell type-specific transcription factor. SpF1-binding sites were also found upstream of the Spec2a and Spec2c genes in the same conserved sequence block as Spec1. Extracts from Lytechinus pictus embryos showed an SpF1-like activity, suggesting that SpF1 is conserved in sea urchins. Surprisingly, changes in the Spec1, Spec2a, or Spec2c genes that removed or modified the SpF1-binding site had no effect on expression when reporter gene fusions containing these mutations were injected into sea urchin eggs and analyzed for expression during embryogenesis. We propose that, while SpF1 may not be essential for expression of the exogenously introduced reporter genes, it may be required for proper regulation of the endogenous Spec genes.

TOXIC EFFECTS OF POLYCHLORINATED BIPHENYL BIOACCUMULATION IN SEA URCHINS EXPOSED TO CONTAMINATED SEDIMENTS

2003 ◽  
Vol 22 (5) ◽  
pp. 1065
Author(s):  
Eddy Y. Zeng ◽  
Steven M. Bay ◽  
Darrin Greenstein ◽  
Cherrie Vista ◽  
Charlie Yu ◽  
...  
Keyword(s):  
Polychlorinated Biphenyl ◽  
Sea Urchins ◽  
Contaminated Sediments ◽  
Toxic Effects

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

Zygote ◽  
2015 ◽  
Vol 24 (3) ◽  
pp. 371-377 ◽  
Author(s):  
Jing Liang ◽  
Heghush Aleksanyan ◽  
Stan Metzenberg ◽  
Steven B. Oppenheimer
Keyword(s):  
Sea Urchin ◽  
Sea Urchins ◽  
Competitive Inhibitor ◽  
Innate Immune ◽  
Lytechinus Pictus ◽  
Sea Urchin Embryo ◽  
Low Concentrations ◽  
Health And Disease ◽  
Dose Dependent ◽  
Dose Dependent Effect

SummaryThe 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.

scholarly journals Exogenous hyalin and sea urchin gastrulation. Part III: Biological activity of hyalin isolated from Lytechinus pictus embryos

Zygote ◽  
2008 ◽  
Vol 16 (4) ◽  
pp. 355-361 ◽  
Author(s):  
Azalia Contreras ◽  
John Vitale ◽  
Virginia Hutchins-Carroll ◽  
Edward J. Carroll ◽  
Steven B. Oppenheimer
Keyword(s):  
Sea Urchin ◽  
Sea Urchins ◽  
National Institutes Of Health ◽  
Cellular Interactions ◽  
General Role ◽  
Lytechinus Pictus ◽  
Sea Urchin Embryo ◽  
Repeat Domain ◽  
Health And Disease ◽  
Adhesive Interactions

SummaryHyalin is a large glycoprotein, consisting of the hyalin repeat domain and non-repeated regions, and is the major component of the hyaline layer in the early sea urchin embryo of Strongylocentrotus purpuratus. The hyalin repeat domain has been identified in proteins from organisms as diverse as bacteria, sea urchins, worms, flies, mice and humans. While the specific function of hyalin and the hyalin repeat domain is incompletely understood, many studies suggest that it has a functional role in adhesive interactions. In part I of this series, we showed that hyalin isolated from the sea urchin S. purpuratus blocked archenteron elongation and attachment to the blastocoel roof occurring during gastrulation in S. purpuratus embryos, (Razinia et al., 2007). The cellular interactions that occur in the sea urchin, recognized by the U.S. National Institutes of Health as a model system, may provide insights into adhesive interactions that occur in human health and disease. In part II of this series, we showed that S. purpuratus hyalin heterospecifically blocked archenteron–ectoderm interaction in Lytechinus pictus embryos (Alvarez et al., 2007). In the current study, we have isolated hyalin from the sea urchin L. pictus and demonstrated that L. pictus hyalin homospecifically blocks archenteron–ectoderm interaction, suggesting a general role for this glycoprotein in mediating a specific set of adhesive interactions. We also found one major difference in hyalin activity in the two sea urchin species involving hyalin influence on gastrulation invagination.

Tubulin polymerization in unfertilized sea-urchin eggs induced by elevated temperature

1989 ◽  
Vol 93 (1) ◽  
pp. 9-17
Author(s):  
P.J. Harris ◽  
E.L. Clason ◽  
K.R. Prier
Keyword(s):  
Elevated Temperature ◽  
Sea Urchins ◽  
Fine Crystal ◽  
Lytechinus Pictus ◽  
Spontaneous Polymerization ◽  
Rate Of Polymerization ◽  
Normal Environment ◽  
Long Term Observation ◽  
Order Structures

Spontaneous polymerization of tubulin was induced in unfertilized eggs of the sea urchins Lytechinus pictus and Strongylocentrotus purpuratus by warming to temperatures 10–12 deg. C above the normal environment for each species. Indirect immunofluorescence microscopy showed that over a period of several hours polymerization proceeded from a fine crystal-like precipitate to larger and fewer higher-order structures. These structures differed morphologically between the two species: L. pictus formed cytasters, while S. purpuratus most often formed flame-like arrays. Nuclear cycles were not initiated, permitting long-term observation of steady-state polymer redistribution. After several hours only a few very large cytasters remained near the surface of L. pictus eggs and these tended to constrict to form protrusions or occasionally a cleavage furrow that divided the egg into two fragments. Staining with rhodamine-labeled phalloidin showed that actin was also concentrated in the cytasters, primarily at the periphery of the centrosphere-like regions. L. pictus cytasters could be recycled by repeated cooling and rewarming, and showed an accelerated rate of polymerization with each successive cycle. Cytasters could also be isolated as long as the initial procedures were carried out at the elevated temperature. Washed preparations were stable at room temperature.(ABSTRACT TRUNCATED AT 250 WORDS)

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