Molecular cloning of five individual stage- and tissue-specific mRNA sequences from sea urchin pluteus embryos.

Five developmentally regulated sea urchin mRNA sequences which increase in abundance between the blastula and pluteus stages of development were isolated by molecular cloning of cDNA. The regulated sequences all appeared in moderately abundant mRNA molecules of pluteus cells and represented 4% of the clones tested. There were no regulated sequences detected in the 40% of the clones which hybridized to the most abundant mRNA, and the screening procedures were inadequate to detect possible regulation in the 20 to 30% of the clones presumably derived from rare-class mRNA. The reaction of 32P[cDNA] from blastula and pluteus mRNA to dots of the cloned DNAs on nitrocellulose filters indicated that the mRNAs complementary to the different cloned pluteus-specific sequences were between 3- and 47-fold more prevalent at the pluteus stage than at the blastula stage. Polyadenylated RNA from different developmental stages was transferred from electrophoretic gels to nitrocellulose filters and reacted to the different cloned sequences. The regulated mRNAs were undetectable in the RNA of 3-h embryos, became evident at the hatching blastula stage, and reached a maximum in abundance by the gastrula or pluteus stage. Certain of the clones reacted to two sizes of mRNA which did not vary coordinately with development. Transfers of RNA isolated from each of the three cell layers of pluteus embryos that were reacted to the cloned sequences revealed that two of the sequences were found in the mRNA of all three layers, two were ectoderm specific, and one was endoderm specific. Four of the regulated sequences were complementary to one or two major bands and one to at least 50 bands on Southern transfers of restriction endonuclease-digested total sea urchin DNA.

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Negative Geotaxis in Sea Urchin Larvae: A Possible Role of Mechanoreception in the Late Stages of Development

Journal of Experimental Biology ◽

10.1242/jeb.137.1.141 ◽

1988 ◽

Vol 137 (1) ◽

pp. 141-156 ◽

Cited By ~ 1

Author(s):

Yoshihiro Mogami ◽

Chieko Oobayashi ◽

Tomoko Yamaguchi ◽

Yumi Ogiso ◽

Shoji A. Baba

Keyword(s):

Control Systems ◽

Sea Urchin ◽

Developmental Stages ◽

Dark Field ◽

Physiological Control ◽

Swimming Direction ◽

Early Stages ◽

Late Stages ◽

Pluteus Stage

Negative geotactic behaviour of sea urchin larvae at various developmental stages from blastula to pluteus was analysed by means of time-exposure dark-field photography of the swimming behaviour of individual larvae. Significant differences in the patterns of behaviour, such as swimming direction and speed, were demonstrated between the early stages (up to the gastrula) and the pluteus, although larvae at any developmental stage showed negative geotactic migration. Larvae in the early stages swam at speeds that varied as a function of the swimming direction with respect to gravity, faster downwards and slower upwards. This might be predicted from the assumption that vertical locomotion is determined by constant propulsion affected passively by gravity. In the pluteus stage, however, larvae swam at a constant speed in any direction, suggesting that the propulsive activity of swimming plutei is actively controlled depending on the swimming direction. This change in the negative geotactic behaviour of sea urchin larvae in the course of embryogenesis indicates development of physiological control systems for propulsive activity at the pluteus stage.

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Molecular cloning and characterization of the full-length cDNA encoding the developmentally regulated lysosomal enzyme beta-glucosidase in Dictyostelium discoideum.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(17)42280-0 ◽

1994 ◽

Vol 269 (2) ◽

pp. 1468-1476

Author(s):

J. Bush ◽

J. Richardson ◽

J. Cardelli

Keyword(s):

Molecular Cloning ◽

Dictyostelium Discoideum ◽

Lysosomal Enzyme ◽

Full Length ◽

Developmentally Regulated ◽

Full Length Cdna ◽

Beta Glucosidase

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Involvement of Huntingtin in Development and Ciliary Beating Regulation of Larvae of the Sea Urchin, Hemicentrotus pulcherrimus

International Journal of Molecular Sciences ◽

10.3390/ijms22105116 ◽

2021 ◽

Vol 22 (10) ◽

pp. 5116

Author(s):

Hideki Katow ◽

Tomoko Katow ◽

Hiromi Yoshida ◽

Masato Kiyomoto

Keyword(s):

Sea Urchin ◽

The Body ◽

Brdu Incorporation ◽

Wild Type ◽

Blastula Stage ◽

Ciliary Beating ◽

Marker Proteins ◽

Disease Protein ◽

Pattern Regulation ◽

Hemicentrotus Pulcherrimus

The multiple functions of the wild type Huntington’s disease protein of the sea urchin Hemicentrotus pulcherrimus (Hp-Htt) have been examined using the anti-Hp-Htt antibody (Ab) raised against synthetic oligopeptides. According to immunoblotting, Hp-Htt was detected as a single band at around the 350 kDa region at the swimming blastula stage to the prism larva stage. From the 2-arm pluteus stage (2aPL), however, an additional smaller band at the 165 kDa region appeared. Immunohistochemically, Hp-Htt was detected in the nuclei and the nearby cytoplasm of the ectodermal cells from the swimming blastula stage, and the blastocoelar cells from the mid-gastrula stage. The Ab-positive signal was converged to the ciliary band-associated strand (CBAS). There, it was accompanied by several CBAS-marker proteins in the cytoplasm, such as glutamate decarboxylase. Application of Hp-Htt morpholino (Hp-Htt-MO) has resulted in shortened larval arms, accompanied by decreased 5-bromo-2-deoxyuridin (BrdU) incorporation by the ectodermal cells of the larval arms. Hp-Htt-MO also resulted in lowered ciliary beating activity, accompanied by a disordered swirling pattern formation around the body. These Hp-Htt-MO-induced deficiencies took place after the onset of CBAS system formation at the larval arms. Thus, Hp-Htt is involved in cell proliferation and the ciliary beating pattern regulation signaling system in pluteus larvae.

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MOLECULAR CLONING OF MOLONEY MOUSE SARCOMA VIRUS SPECIFIC SEQUENCES FROM UNINFECTED MOUSE CELLS

Animal Virus Genetics ◽

10.1016/b978-0-12-255850-4.50045-7 ◽

1980 ◽

pp. 461-471

Author(s):

Matt Jones ◽

Robert A. Bosselman ◽

Frans V.d. Hoorn ◽

Anton Berns ◽

Inder M. Verma

Keyword(s):

Molecular Cloning ◽

Uninfected Mouse ◽

Mouse Sarcoma ◽

Sarcoma Virus ◽

Mouse Cells ◽

Specific Sequences ◽

Mouse Sarcoma Virus

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The Centriole-Centrosome Complex is Affected by Microgravity During Cell Division and in Cilia of Sea Urchin Embryos: Results from Space Flight Experiments

Microscopy and Microanalysis ◽

10.1017/s1431927600025782 ◽

1998 ◽

Vol 4 (S2) ◽

pp. 1132-1133

Author(s):

Heide Schatten ◽

Amitabha Chakrabarti ◽

Meghan Taylor ◽

Michael Crosser ◽

Kirk Mitchell

Keyword(s):

Cell Division ◽

Sea Urchin ◽

Space Flight ◽

Space Shuttle ◽

Sea Urchins ◽

Culture Conditions ◽

Model System ◽

Research Facility ◽

Cilia Formation ◽

Pluteus Stage

Sea urchins have been used for over a century as a remarkable animal model system in which to study cell, molecular, and developmental biology. The studies presented here have used sea urchin eggs and embryos for pioneering experiments to explore the effects of microgravity on the cytoskeleton during a space flight on the space shuttle Endeavor. The culture conditions followed those described previously utilizing the Aquatic Research Facility (ARF) to fertilize and culture eggs and embryos up to the pluteus stage under controlled temperature (12°C) and fixation conditions. To achieve a final fixation with 0.5% glutaraldehyde and 4μM taxol, concentrated fixation fluid was injected at preselected time points to preserve microtubules, centrioles, centrosomes, microfilaments, mitochondria, and cell membranes.The analysis of the results revealed that the centriole-centrosome complex during cell division and cilia formation showed alterations in samples that had been exposed to microgravity while control cells cultured in a centrifuge at lg in space and those cultured on ground appeared normal.

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Origin and behaviour of pigment cells in sea urchin embryos

Zygote ◽

10.1017/s0967199400130205 ◽

1999 ◽

Vol 8 (S1) ◽

pp. S42-S43 ◽

Cited By ~ 1

Author(s):

Tetsuya Kominami

Keyword(s):

Sea Urchin ◽

Pigment Cell ◽

Cell Lineage ◽

Pigment Cells ◽

Cleavage Stage ◽

Fate Map ◽

Blastula Stage ◽

Cell Stage ◽

Stage Embryo ◽

Founder Cells

Sea urchin pluteus larvae contain dozens of pigment cells in their ectoderm. These pigment cells are the descendants of the veg2 blastomeres of the 60-cell stage embryo. According to the fate map made by Ruffins and Ettensohn, the prospective pigment cells occupy the central region of the vegetal plate. Most of these prospective pigment cells exclusively give rise to pigment cells. Therefore, specification of the pigment cell lineage should occur at some point between the 60-cell and mesenchyme blastula stage. However, the detailed process of the specification of the pigment lineage is unknown.When are pigment cells specified? Are cell interactions necessary for the specification? Do founder cells exist? To answer these questions, I treated embryos with Ca2+-free seawater during the cleavage stage and examined the number of pigment cells observed in pluteus larvae. Treatment at 5.5–8.5 h and especially 7.5–10.5 h postfertilisation markedly reduced the number of pigment cells. The decrease was statistically significant. On the other hand, the treatment at 3.5–6.5 h or 9.5–12.5 h never reduced the number of pigment cells. By examining the frequency of the appearance of embryos whose numbers of pigment cells were less than 20, it was also found that the numbers of pigment cells were frequently in multiples of 4. Embryos having 4, 8, 12, 16 and 20 pigment cells were more frequently observed. Statistics indicated that the frequency of appearance was not random. These results indicated that cell contacts are necessary for the specification of pigment cells and that the specification occurs from 7 to 10 h postfertilisation. The results also suggest that the founder cells, if they exist, divide twice before they differentiate into pigment cells.

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