Temporal and spatial occurrence of UV-absorbing mycosporine-like amino acids in tissues of the antarctic sea urchin Sterechinusneumayeri during springtime ozone-depletion

1997 ◽  
Vol 129 (2) ◽  
pp. 343-353 ◽  
Author(s):  
D. Karentz ◽  
W. C. Dunlap ◽  
I. Bosch
1971 ◽  
Vol 50 (2) ◽  
pp. 516-528 ◽  
Author(s):  
Rudolf A. Raff ◽  
Gerald Greenhouse ◽  
Kenneth W. Gross ◽  
Paul R. Gross

Studies employing colchicine binding, precipitation with vinblastine sulfate, and acrylamide gel electrophoresis confirm earlier proposals that Arbacia punctulata and Lytechinus pictus eggs and embryos contain a store of microtubule proteins. Treatment of 150,000 g supernatants from sea urchin homogenates with vinblastine sulfate precipitates about 5% of the total soluble protein, and 75% of the colchicine-binding activity. Electrophoretic examination of the precipitate reveals two very prominent bands. These have migration rates identical to those of the A and B microtubule proteins of cilia. These proteins can be made radioactive at the 16 cell stage and at hatching by pulse labeling with tritiated amino acids. By labeling for 1 hr with leucine-3H in early cleavage, then culturing embryos in the presence of unlabeled leucine, removal of newly synthesized microtubule proteins from the soluble pool can be demonstrated. Incorporation of labeled amino acids into microtubule proteins is not affected by culturing embryos continuously in 20 µg/ml of actinomycin D. Microtubule proteins appear, therefore, to be synthesized on "maternal" messenger RNA. This provides the first protein encoded by stored or "masked" mRNA in sea urchin embryos to be identified.


Development ◽  
1971 ◽  
Vol 26 (3) ◽  
pp. 611-622
Author(s):  
Maya R. Krigsgaber ◽  
Alla A. Kostomarova ◽  
Tamara A. Terekhova ◽  
Tatiana A. Burakova

Synthesis of nuclear and cytoplasmic proteins was studied biochemically and autoradiographically in early loach (Misgurnus fossilis) and sea-urchin (Strongylocentrotus nudus) embryos. After incubation with [14C]amino acids for 5–120 min the ratio of the specific activities of nuclear, mitochondrial and 12000 g supernatant proteins was shown to be equal approximately to 6:1:2 in loach embryos and to 8:4:3 in sea-urchin embryos independently of the duration of labelling. After incubation with [3H]amino acids the number of silver grains per unit section was on the average 2·4 times higher for nuclei than it was for cytoplasm at mid-blastula and mid-gastrula stages. At the mid-gastrula the vegeto-animal gradient of protein synthesis was found. A higher level of the synthesis of nuclear proteins as compared with that of cytoplasmic proteins appears to be related to an increase in the nuclear volume and the nucleo-cytoplasmic ratio during the early development of the loach and sea-urchin embryos.


Development ◽  
1995 ◽  
Vol 121 (5) ◽  
pp. 1497-1505 ◽  
Author(s):  
A.H. Wikramanayake ◽  
B.P. Brandhorst ◽  
W.H. Klein

During early embryogenesis, the highly regulative sea urchin embryo relies extensively on cell-cell interactions for cellular specification. Here, the role of cellular interactions in the temporal and spatial expression of markers for oral and aboral ectoderm in Strongylocentrotus purpuratus and Lytechinus pictus was investigated. When pairs of mesomeres or animal caps, which are fated to give rise to ectoderm, were isolated and cultured they developed into ciliated embryoids that were morphologically polarized. In animal explants from S. purpuratus, the aboral ectoderm-specific Spec1 gene was activated at the same time as in control embryos and at relatively high levels. The Spec1 protein was restricted to the squamous epithelial cells in the embryoids suggesting that an oral-aboral axis formed and aboral ectoderm differentiation occurred correctly. However, the Ecto V protein, a marker for oral ectoderm differentiation, was detected throughout the embryoid and no stomodeum or ciliary band formed. These results indicated that animal explants from S. purpuratus were autonomous in their ability to form an oral-aboral axis and to differentiate aboral ectoderm, but other aspects of ectoderm differentiation require interaction with vegetal blastomeres. In contrast to S. purpuratus, aboral ectoderm-specific genes were not expressed in animal explants from L. pictus even though the resulting embryoids were morphologically very similar to those of S. purpuratus. Recombination of the explants with vegetal blastomeres or exposure to the vegetalizing agent LiCl restored activity of aboral ectoderm-specific genes, suggesting the requirement of a vegetal induction for differentiation of aboral ectoderm cells.(ABSTRACT TRUNCATED AT 250 WORDS)


Author(s):  
Karina González ◽  
Juan Gaitán-Espitia ◽  
Alejandro Font ◽  
César A. Cárdenas ◽  
Marcelo González-Aravena

2018 ◽  
Vol 56 (4A) ◽  
pp. 30
Author(s):  
Kim Hoa Thi Dinh

ABSTRACT – HCTN 06The Sea urchin Tripneustes gratilla (Linnaeus, 1758) is a famous species of invertebrate member of the phylum Echinodermata of marine animals living in shallow tropical water. In Viet Nam, it is usually called by the name of yellow sea urchin. This species is mentioned much about its economic and commerce properties. Recently, many researchers have been paying attention to sea urchin because of its positive effect on human health. In terms of medicine and nutrition, the egg of yellow sea urchin was rich in Polyunsaturated Fatty Acids (PUFAs) and essential amino acids. In this research, we focused on determining the total lipid contents, the components of lipid classes and the compositions and contents of fatty acids, amino acids from the body and the egg of the yellow sea urchin T. gratilla (Linnaeus, 1758) collected in Hon Tam, Nha Trang, Khanh Hoa, Viet Nam in 2016. Although the yellow sea urchin T. gratilla has low percentage of total lipid in fresh weigh basis, they are full of essential lipid ingredients such as Wax and Hydrocabon (H + W), Triacylglycerol (TG), Monodiacylglycerol MDAG, Free Fatty Acid (FFA), sterol (ST), and Polar Lipid (PL). In both egg and body samples palmitic acid (16:0) was the most abundant fatty acid with the proportion of about 25%. In addition, arachidonic acid (20:4n-6) is dominent Omega-6 fatty acid in the Monounsaturated Fatty Acid group (MUFA). Furthermore, the research result also showed the very high percentages of omega-3 fatty acids in the egg and body of T. gratilla, with the total contents of 13.97% and 20.67% respectively, especially the presence of eicosapentaenoic fatty acid (C20:5n-3, EPA), a very valuable fatty acid. By the HPLC method, the research also found 17 amino acids in the egg and body of T. gratilla with the existence of 7 essential amino acids.Keywords: Tripneustes gratilla, lipid classes, yellow sea urchin, echinodermata, fatty acid content. 


1968 ◽  
Vol 3 (4) ◽  
pp. 515-527
Author(s):  
J. PIATIGORSKY ◽  
A. TYLER

Unfertilized and fertilized eggs of the sea urchin Lytechinus pictus were preloaded with [14C]valine and exposed to individual solutions of each of the twenty ‘coded’ [12C]amino acids in artificial sea water. After 1 h incubation the amount of radioactivity in the medium was determined. The radioactivity was effectively displaced by most of the other neutral [12C]amino acids that are known to compete with valine for uptake. A chromatographic test with fertilized eggs showed the displaced radioactivity to be [14C]valine and not some metabolic product. Addition of acidic, basic or some neutral amino acids that are known to be poor inhibitors of valine uptake did not cause significant quantities of label to appear in the medium. For the unfertilized eggs, the concentration of acid-soluble label remained many hundreds of times greater in the egg fluid than in the sea water. Tests indicated that efflux of [14C]valine and subsequent competition for re-entry is a primary factor responsible for the displacement phenomenon. That this may not be the sole factor is suggested by the fact that some amino acids that are known to be powerful inhibitors of valine uptake were found to be only weak displacers of [14C]valine. Neither [14C]arginine nor [14C]glutamic acid were displaced in significant amounts from preloaded unfertilized or fertilized eggs by any of the tested [12C]amino acids. Attempts were made to utilize the displacement of [12C]valine to elevate the incorporation of [14C]valine and of other labelled amino acids into protein by intact eggs. Unfertilized and fertilized eggs were pretreated with related [12C]amino acids and then exposed to [14C]valine or a mixture of [14C]amino acids. The results varied in the different tests, ranging from no significant increase to 2-fold.


Polar Biology ◽  
2019 ◽  
Vol 42 (4) ◽  
pp. 743-757 ◽  
Author(s):  
E. Bergami ◽  
A. Krupinski Emerenciano ◽  
M. González-Aravena ◽  
C. A. Cárdenas ◽  
P. Hernández ◽  
...  

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