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Wang Z, Lv Z, Li C, Shao Y, Zhang W, Zhao X. An invertebrate β-integrin mediates coelomocyte phagocytosis via activation of septin2 and 7 but not septin10. Int J Biol Macromol 2018. [DOI: 10.1016/j.ijbiomac.2018.03.033] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Moorhouse KS, Gudejko HF, McDougall A, Burgess DR. Influence of cell polarity on early development of the sea urchin embryo. Dev Dyn 2015; 244:1469-84. [PMID: 26293695 PMCID: PMC4715636 DOI: 10.1002/dvdy.24337] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2015] [Revised: 08/11/2015] [Accepted: 08/13/2015] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Establishment and maintenance of cell polarity is critical for normal embryonic development. Previously, it was thought that the echinoderm embryo remained relatively unpolarized until the first asymmetric division at the 16-cell stage. Here, we analyzed roles of the cell polarity regulators, the PAR complex proteins, and how their disruption in early development affects later developmental milestones. RESULTS We found that PAR6, aPKC, and CDC42 localize to the apical cortex as early as the 2-cell stage and that this localization is retained through the gastrula stage. Of interest, PAR1 also colocalizes with these apical markers through the gastrula stage. Additionally, PAR1 was found to be in complex with aPKC, but not PAR6. PAR6, aPKC, and CDC42 are anchored in the cortical actin cytoskeleton by assembled myosin. Furthermore, assembled myosin was found to be necessary to maintain proper PAR6 localization through subsequent cleavage divisions. Interference with myosin assembly prevented the embryos from reaching the blastula stage, while transient disruptions of either actin or microtubules did not have this effect. CONCLUSIONS These observations suggest that disruptions of the polarity in the early embryo can have a significant impact on the ability of the embryo to reach later critical stages in development.
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Affiliation(s)
- Kathleen S. Moorhouse
- Department of Biology, Boston College, Chestnut Hill, Massachusetts
- Marine Biological Laboratory, Woods Hole, Massachusetts
| | - Heather F.M. Gudejko
- Department of Biology, Boston College, Chestnut Hill, Massachusetts
- Marine Biological Laboratory, Woods Hole, Massachusetts
| | - Alex McDougall
- UMR 7009, UPMC Sorbonne Universités, Centre National de la Recherche (CNRS), Observatoire Océanologique, 181 Chemin du Lazaret, 06230 Villefranche-sur-Mer, France
| | - David R. Burgess
- Department of Biology, Boston College, Chestnut Hill, Massachusetts
- Marine Biological Laboratory, Woods Hole, Massachusetts
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3
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Chan D, Thomas CJ, Taylor VJ, Burke RD. Integrins on eggs: focal adhesion kinase is activated at fertilization, forms a complex with integrins, and is necessary for cortex formation and cell cycle initiation. Mol Biol Cell 2013; 24:3472-81. [PMID: 23985318 PMCID: PMC3814141 DOI: 10.1091/mbc.e13-03-0148] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 07/31/2013] [Accepted: 08/20/2013] [Indexed: 12/12/2022] Open
Abstract
We investigate the proposal that integrins and focal adhesion kinase (FAK) form a complex that has structural and signaling functions in eggs. FAK protein is present in eggs and is phosphorylated at fertilization. pY(397)FAK localizes to the membrane 30 min after fertilization, which correlates with the expression of βC integrins and egg cortex development. The βC integrin and pY(397)FAK coimmunoprecipitate from egg cortex lysates. PF573 228 and Y11, inhibitors of FAK, interfere with pronuclear fusion and reduce the abundance of pY(397)FAK and cortical actin without affecting microvillar actin. Cyclin E normally accumulates in the nucleus 15 min after fertilization, then returns to background levels. PF573 228- or Y11-treated eggs accumulate cyclin E in the nucleus; however, levels remain high. In addition, PF573 228 interferes with the accumulation of pERK1/2 in the nucleus and in eggs initiating mitosis. Injection of eggs with a fusion protein consisting of the focal adhesion-targeting domain of FAK fused to green fluorescent protein interferes with cortex formation and produces abnormal nuclei. These data indicate that an integrin-FAK adhesion complex forms at the egg surface that functions in formation of actin arrays in the egg cortex and provides signaling inputs for cell cycle initiation.
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Affiliation(s)
- D. Chan
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8P 5C2, Canada
| | - C. J. Thomas
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8P 5C2, Canada
| | - V. J. Taylor
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8P 5C2, Canada
| | - R. D. Burke
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8P 5C2, Canada
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4
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Roles for focal adhesion kinase (FAK) in blastomere abscission and vesicle trafficking during cleavage in the sea urchin embryo. Mech Dev 2013; 130:290-303. [PMID: 23313141 DOI: 10.1016/j.mod.2012.12.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2011] [Revised: 12/23/2012] [Accepted: 12/27/2012] [Indexed: 11/23/2022]
Abstract
Is focal adhesion kinase (FAK) needed for embryonic cleavage? We find that FAK is expressed during early cleavage divisions of sea urchin embryos as determined by polyclonal antibodies to the Lytechinus variegatus protein. FAK is absent in eggs and zygotes and then cycles in abundance during the first cleavages after fertilization. It is maximal at anaphase, similar to the destruction and synthesis of cyclin proteins. To investigate whether FAK is needed during early cleavage, we interfered with its function by microinjecting eggs with anti-FAK antibodies or with FAK antisense morpholino oligonucleotides. Both treatments led to regression of the cleavage furrow. FAK knockdown with antibodies or morpholino oligonucleotides also resulted in an over-accumulation of endocytic vesicles. Thus, FAK could be restricting endocytosis or increasing exocytosis in localized areas important for abscission. FAK appears to be necessary for successful cleavage. These results are the first to document a functional role for FAK during embryonic cleavage.
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Actinoporins from the sea anemones, tropical Radianthus macrodactylus and northern Oulactis orientalis: Comparative analysis of structure–function relationships. Toxicon 2010; 56:1299-314. [DOI: 10.1016/j.toxicon.2010.07.011] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2009] [Revised: 07/16/2010] [Accepted: 07/19/2010] [Indexed: 11/24/2022]
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6
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Zito F, Burke RD, Matranga V. Pl-nectin, a discoidin family member, is a ligand for betaC integrins in the sea urchin embryo. Matrix Biol 2010; 29:341-5. [PMID: 20159038 DOI: 10.1016/j.matbio.2010.02.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Accepted: 02/09/2010] [Indexed: 10/19/2022]
Abstract
Pl-nectin is a component of the extracellular matrix that surrounds embryos of the sea urchin Paracentrotus lividus. Pl-nectin mediates adhesion of dissociated embryonic cells to substrates and interfering with ectodermic cells contacting Pl-nectin results in defects in skeleton growth and morphogenesis. Recently, we reported that Pl-nectin is a new member of the discoidin family, in agreement with the notion that many discoidin-containing proteins are involved in cell adhesion processes as integrin ligands. To better understand the molecular basis for the interaction of Pl-nectin with ectoderm, we investigated the hypothesis that Pl-nectin is an integrin ligand in sea urchin embryos. We show that in P. lividus embryos, betaC-containing integrins localize to the apical surface of ectodermic cells, which are in contact with Pl-nectin. Immunoprecipitation experiments indicate that the two proteins are part of a complex in vivo and affinity chromatography indicates that betaC-containing integrin receptors bind purified Pl-nectin. These data support a model in which ectodermic integrins binding to Pl-nectin mediate cellular adhesion to the hyaline layer. Regulated adhesion of cells to the hyaline layer is a critical component of several morphogenetic processes and the identification of the receptors and ligands involved provides new opportunities to investigate the underlying molecular mechanisms of ECM adhesion and morphogenesis.
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Affiliation(s)
- Francesca Zito
- Consiglio Nazionale delle Ricerche, Istituto di Biomedicina e Immunologia Molecolare Alberto Monroy, Via Ugo La Malfa 153, Palermo, Italy.
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7
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Phylogenetic analysis and homology modelling of Paracentrotus lividus nectin. Mol Divers 2009; 14:653-65. [DOI: 10.1007/s11030-009-9203-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2009] [Accepted: 10/20/2009] [Indexed: 01/21/2023]
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8
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Alford LM, Ng MM, Burgess DR. Cell polarity emerges at first cleavage in sea urchin embryos. Dev Biol 2009; 330:12-20. [PMID: 19298809 DOI: 10.1016/j.ydbio.2009.02.039] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2008] [Revised: 02/24/2009] [Accepted: 02/25/2009] [Indexed: 12/26/2022]
Abstract
In protostomes, cell polarity is present after fertilization whereas most deuterostome embryos show minimal polarity during the early cleavages. We now show establishment of cell polarity as early as the first cleavage division in sea urchin embryos. We find, using the apical markers G(M1), integrins, and the aPKC-PAR6 complex, that cells are polarized upon insertion of distinct basolateral membrane at the first division. This early apical-basolateral polarity, similar to that found in much larger cleaving amphibian zygotes, reflects precocious functional epithelial cell polarity. Isolated cleavage blastomeres exhibit polarized actin-dependent fluid phase endocytosis only on the G(M1), integrin, microvillus-containing apical surface. A role for a functional PAR complex in cleavage plane determination was shown with experiments interfering with aPKC activity, which results in several spindle defects and compromised blastula development. These studies suggest that cell and embryonic polarity is established at the first cleavage, mediated in part by the Par complex of proteins, and is achieved by directed insertion of basolateral membrane in the cleavage furrow.
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Affiliation(s)
- Lea M Alford
- Biology Department, Boston College, 140 Commonwealth Ave., Chestnut Hill, MA 02467, USA
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9
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Abstract
Sea urchin embryos are characterized by an extremely simple mode of development, rapid cleavage, high transparency, and well-defined cell lineage. Although they are not suitable for genetic studies, other approaches are successfully used to unravel mechanisms and molecules involved in cell fate specification and morphogenesis. Microinjection is the elective method to study gene function in sea urchin embryos. It is used to deliver precise amounts of DNA, RNA, oligonucleotides, peptides, or antibodies into the eggs or even into blastomeres. Here we describe microinjection as it is currently applied in our laboratory and show how it has been used in gene perturbation analyses and dissection of cis-regulatory DNA elements.
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10
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Dinkins MB, Fratto VM, Lemosy EK. Integrin alpha chains exhibit distinct temporal and spatial localization patterns in epithelial cells of the Drosophila ovary. Dev Dyn 2009; 237:3927-39. [PMID: 19035354 DOI: 10.1002/dvdy.21802] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Integrins are heterodimeric transmembrane receptors that modulate cell adhesion, migration, and signaling. Multiple integrin chains contribute to development and morphogenesis of a given tissue. Here, we analyze the expression of Drosophila integrin alpha chains in the ovarian follicular epithelium, a model for tissue morphogenesis and cell migration. We find expression throughout development of the beta chain, betaPS. Alpha chains, however, exhibit both spatial and temporal expression differences. alphaPS1 and alphaPS2 integrins are detected during early and mid-oogenesis on apical, lateral, and basal membranes with the betaPS chain, whereas alphaPS3-family integrins (alphaPS3, alphaPS4, alphaPS5) are expressed in anterior cells late in oogenesis. Surprisingly, we find that alphaPS3-family integrins are dispensable for dorsal appendage morphogenesis but play a role in the final length of the egg, suggesting redundant functions of integrins in a simple tissue. We also demonstrate roles for alphaPS3betaPS integrin in border cell migration and in stretch cells.
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Affiliation(s)
- Michael B Dinkins
- Department of Cellular Biology, Medical College of Georgia, 1120 15th Street, CB1101, Augusta, GA 30912, USA
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11
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Abstract
Cleavage divisions in many animals form a blastula made up of a simple polarized epithelium. This simple embryonic epithelium possesses an apical surface covered with microvilli and primary cilia separated from the basolateral surfaces by cell-cell junctions. The apical membrane proteins and lipids differ from those of the basolateral on these embryonic epithelial cells, as is found in adult epithelial cells. Formation of cell polarity in embryos at fertilization, including those from both protostomes and deuterostomes, uses the same molecules and signalling machinery as do polarizing epithelial cells that polarize upon cell-cell contact. In addition, the actin-myosin cytoskeleton plays an integral role in establishment and maintenance of this early cell polarity. However, early cleaving blastomeres from higher organisms including echinoderms and vertebrates have not been considered to exhibit cell polarity until formation of junctions at the third through to the fifth cleavage divisions. The role of new membrane addition into the late cleavage furrow during the early rounds of cytokinesis may play a key role in the early establishment of cell polarity in all animal embryos.
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12
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Whittaker CA, Bergeron KF, Whittle J, Brandhorst BP, Burke RD, Hynes RO. The echinoderm adhesome. Dev Biol 2006; 300:252-66. [PMID: 16950242 PMCID: PMC3565218 DOI: 10.1016/j.ydbio.2006.07.044] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2006] [Revised: 07/19/2006] [Accepted: 07/31/2006] [Indexed: 12/21/2022]
Abstract
Although the development of sea urchin embryos has been studied extensively and clearly involves both cell adhesion and cell migration, rather little is known about the adhesion receptors and extracellular matrix molecules involved. The completion of the genome of Strongylocentrotus purpuratus allows a comprehensive survey of the complement of cell-cell and cell-matrix adhesion molecules in this organism. Furthermore, the phylogenetic position of echinoderms offers the opportunity to compare the complement of adhesion proteins between protostome and deuterostome invertebrates and between invertebrate and vertebrate deuterostomes. Many aspects of development and cell interactions differ among these different taxa and it is likely that analysis of the spectrum of adhesion receptors and extracellular matrix proteins can open up new insights into which molecules have evolved to suit particular developmental processes. In this paper, we report the results of an initial analysis along these lines. The echinoderm adhesome (complement of adhesion-related genes/proteins) is similar overall to that of other invertebrates although there are significant deuterostome-specific innovations and some interesting features previously thought to be chordate or vertebrate specific.
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Affiliation(s)
| | - Karl-Frederik Bergeron
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, V5A1S6, Canada
| | - James Whittle
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Bruce P. Brandhorst
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, V5A1S6, Canada
| | - Robert D. Burke
- Dept of Biology, Dept of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8W 3N5, Canada
| | - Richard O. Hynes
- Center for Cancer Research, Cambridge, MA 02139, USA
- Howard Hughes Medical Institute, Cambridge, MA 02139, USA
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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13
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Roux MM, Townley IK, Raisch M, Reade A, Bradham C, Humphreys G, Gunaratne HJ, Killian CE, Moy G, Su YH, Ettensohn CA, Wilt F, Vacquier VD, Burke RD, Wessel G, Foltz KR. A functional genomic and proteomic perspective of sea urchin calcium signaling and egg activation. Dev Biol 2006; 300:416-33. [PMID: 17054939 DOI: 10.1016/j.ydbio.2006.09.006] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2006] [Revised: 09/01/2006] [Accepted: 09/02/2006] [Indexed: 01/02/2023]
Abstract
The sea urchin egg has a rich history of contributions to our understanding of fundamental questions of egg activation at fertilization. Within seconds of sperm-egg interaction, calcium is released from the egg endoplasmic reticulum, launching the zygote into the mitotic cell cycle and the developmental program. The sequence of the Strongylocentrotus purpuratus genome offers unique opportunities to apply functional genomic and proteomic approaches to investigate the repertoire and regulation of Ca(2+) signaling and homeostasis modules present in the egg and zygote. The sea urchin "calcium toolkit" as predicted by the genome is described. Emphasis is on the Ca(2+) signaling modules operating during egg activation, but the Ca(2+) signaling repertoire has ramifications for later developmental events and adult physiology as well. Presented here are the mechanisms that control the initial release of Ca(2+) at fertilization and additional signaling components predicted by the genome and found to be expressed and operating in eggs at fertilization. The initial release of Ca(2+) serves to coordinate egg activation, which is largely a phenomenon of post-translational modifications, especially dynamic protein phosphorylation. Functional proteomics can now be used to identify the phosphoproteome in general and specific kinase targets in particular. This approach is described along with findings to date. Key outstanding questions regarding the activation of the developmental program are framed in the context of what has been learned from the genome and how this knowledge can be applied to functional studies.
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Affiliation(s)
- Michelle M Roux
- Department MCD Biology and Marine Science Institute, University of California, Santa Barbara, CA 93106-9610, USA
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Nair SV, Del Valle H, Gross PS, Terwilliger DP, Smith LC. Macroarray analysis of coelomocyte gene expression in response to LPS in the sea urchin. Identification of unexpected immune diversity in an invertebrate. Physiol Genomics 2005; 22:33-47. [PMID: 15827237 DOI: 10.1152/physiolgenomics.00052.2005] [Citation(s) in RCA: 129] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The purple sea urchin, Strongylocentrotus purpuratus, is a member of the phylum Echinodermata, which is basal to the phylum Chordata within the deuterostome lineage of the animal kingdom. This relationship makes the analysis of the sea urchin immune system relevant to understanding the evolution of the deuterostome immune system leading to the Vertebrata. Subtractive suppression hybridization was employed to generate cDNA probes for screening high-density arrayed, conventional cDNA libraries to identify genes that were upregulated in coelomocytes responding to lipopolysaccharide. Results from 1,247 expressed sequence tags (ESTs) were used to infer that coelomocytes upregulated genes involved in RNA splicing, protein processing and targeting, secretion, endosomal activities, cell signaling, and alterations to the cytoskeletal architecture including interactions with the extracellular matrix. Of particular note was a set of transcripts represented by 60% of the ESTs analyzed, which encoded a previously uncharacterized family of closely related proteins, provisionally designated as 185/333. These transcripts exhibited a significant level of variation in their nucleotide sequence and evidence of putative alternative splicing that could yield up to 15 translatable elements. On the basis of the striking increase in gene expression in response to lipopolysaccharide and the unexpected level of diversity of the 185/333 messages, we propose that this set of transcripts encodes a family of putative immune response proteins that may represent a major component of an immunological response to bacterial challenge.
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Affiliation(s)
- Sham V Nair
- Department of Biological Sciences, George Washington University, Washington, District of Columbia 20052, USA
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Tsabar N, Gefen A, Elias S, Frank D. Aggregation of maternal pigment granules is induced by the cytosolic discoidin domain of theXenopus Del1 protein. Dev Dyn 2005; 233:224-32. [PMID: 15765521 DOI: 10.1002/dvdy.20308] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Xenopus oocytes generate pigment granules (melanosomes) that predominantly localize to the animal hemisphere cortex. During embryonic development, these granules are located near the membranes of outer layer ectoderm cells. We report a novel phenotype found during an expression cloning screen in Xenopus laevis embryos. The phenotype is characterized by dissociation of pigment granules from the cell membrane to form large central aggregates. This phenomenon was induced by a truncated form of the Xenopus Del1 (XDel1) protein that contains only the C-terminal discoidin (D2) domain. This truncated form of XDel1 localized to membranes as shown by a chimeric enhanced green fluorescent protein construct. Although a similar localization occurred in immature oocytes, dissociation of pigment granules was limited to the oocyte vegetal hemisphere. The full-length XDel1 cDNA was cloned, and XDel1 mRNA expression was found to be ubiquitous and continuous from early oocyte to tail bud stages, with a transient enrichment in the cement gland. Ectopic expression of various deletion or full-length constructs or antisense morpholino oligonucleotides did not induce any significant developmental phenotypes.
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Affiliation(s)
- Nir Tsabar
- Department of Biochemistry, The Rappaport Family Institute for Research in the Medical Sciences, Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
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Haley SA, Wessel GM. Proteolytic cleavage of the cell surface protein p160 is required for detachment of the fertilization envelope in the sea urchin. Dev Biol 2004; 272:191-202. [PMID: 15242800 DOI: 10.1016/j.ydbio.2004.03.043] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2003] [Revised: 02/20/2004] [Accepted: 03/25/2004] [Indexed: 12/01/2022]
Abstract
Sea urchin eggs secrete a serine protease activity, CGSP1, at fertilization that is essential for the block to polyspermy. Several targets of this proteolytic activity on the plasma membrane were identified here using a cell surface biotinylation approach. Amino acid microsequencing of one of these proteins led to the identification of a 4.75-kb cDNA clone from a Strongylocentrotus purpuratus ovary cDNA library that encodes a 160-kDa protein called p160. This protein contains five CUB domains and a putative transmembrane domain suggesting that p160 is an integral membrane protein with protein-protein interaction motifs facing the extracellular matrix of the egg. Whole-mount immunolocalization studies demonstrate that p160 is on the surface of the egg, enriched at the tips of microvilli. The protein is removed at fertilization in a protease-dependent manner, and functional assays suggest that p160 serves to link the plasma membrane to the vitelline layer until fertilization. Thus, p160 is a key candidate for a vitelline-layer linker protein, the selective proteolysis of which functions in the block to polyspermy in the sea urchin egg.
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Affiliation(s)
- Sheila A Haley
- Department of Molecular and Cellular Biology and Biochemistry, Brown University, Providence, RI 02912, USA
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