Chapter 4 Phenomena of Cellular Recognition in Sponges

Vyver, Gysèle Van de

doi:10.1016/s0070-2153(08)60040-x

Cited by 50 publications

(23 citation statements)

References 28 publications

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“…Mixtures of cells dissociated from different individuals of the freshwater sponge Ephydatia fluviatilis segregated into clumps containing cells of only one individual several days after a mixed aggregate was formed (33). Such individual specificity could be also observed between cell fractions containing only one cell type (34).…”

Section: Discussionmentioning

confidence: 80%

Accumulation in Marine Sponge Grafts of the mRNA Encoding the Main Proteins of the Cell Adhesion System

Fernàndez‐Busquets¹,

Gerosa²,

Heß

et al. 1998

Journal of Biological Chemistry

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Specific cell adhesion in the marine sponge Microciona prolifera is mediated by an extracellular aggregation factor complex, whose main protein component, termed MAFp3, is highly polymorphic. We have now identified MAFp4, an ϳ400-kDa protein, from the aggregation factor that is translated from the same mRNA as MAFp3. The existence of multiple potential sites for Nglycosylation and calcium binding suggests a direct involvement of MAFp4 in the species-specific aggregation of sponge cells. The deduced partial polypeptide consists of a 16-fold reiterated motif that shows significant similarity to a repeat in an endoglucanase from the symbiontic bacterium Azorhizobium caulinodans and to the intracellular loop of mammalian Na ؉ -Ca 2؉ exchangers. Restriction fragment length polymorphism analysis indicated that the genomic variability of MAFp4 is high and comparable to that of MAFp3. Their combined polymorphism correlates with allogeneic responses studied in a population of 23 sponge individuals. Peptide mass fingerprinting of tryptic digests of the polymorphic MAFp3 bands observed on polyacrylamide gels after chemical deglycosylation of the Microciona aggregation factor revealed that the variability detected on Southern blots at least partially reflects the individual variability of aggregation factor protein components. Polyclonal antibodies raised against MAFp3 strongly crossreacted with a 68-kDa protein localized in sponge cell membranes. Immunohistochemical use of the antiMAFp3 antibodies strongly stained a cell layer along the line of contact in allogeneic grafts. We show that the transcription level of the MAFp3/MAFp4 mRNA in sponge allo-and isografts is clearly increased in comparison with non-grafted tissue. These data are discussed with respect to a possible evolutionary relationship between cell adhesion and histocompatibility systems.Species-specific cell recognition in sponges is mediated by proteoglycan-like extracellular complexes termed aggregation factors (AFs), 1 unidentified so far in other phyla, although Northern blots suggested the existence, in several human tissues, of proteins related to those found in the AF of the marine sponge Microciona prolifera (1). Cell adhesion in this species is mediated by calcium-dependent carbohydrate interactions of homologous Microciona AF (MAF) molecules via N-linked glycans. A proposed model suggested that species specificity could be at least partially provided by the different spacing of glycosaminoglycan chains on the protein core (2), thus postulating the existence of a different AF core protein in each species. Unexpectedly, an extraordinarily high intraspecific variability was found for the MAF core protein (1), suggesting that AFs might also be involved in individual specificity.The immune and cell adhesion systems are clearly related, as deduced from phylogenetic relationships between molecules of both groups (3) and as expected from the fact that the cells of the immune system depend on regulated interactions with other cells to be activated (4). An evo...

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Section: Discussionmentioning

confidence: 80%

Accumulation in Marine Sponge Grafts of the mRNA Encoding the Main Proteins of the Cell Adhesion System

Fernàndez‐Busquets¹,

Gerosa²,

Heß

et al. 1998

Journal of Biological Chemistry

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“…The cell aggregation activity of marine AFs depends on an extracellular calcium concentration of about 10 mM, similar to that found in sea water. AFs from freshwater sponges have also been described [104] and partially purified [105,106], although they are still poorly characterized. Freshwater sponge AFs are active at Ca 2+ concentrations of 1 mM [107], implying major differences when compared to their marine counterparts.…”

Section: Sponge Pgs In Cell Adhesionmentioning

confidence: 99%

Circular proteoglycans from sponges: first members of the spongican family

Fernàndez‐Busquets

Burger

2003

Cellular and Molecular Life Sciences (CMLS)

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Species-specific cell adhesion in marine sponges is mediated by a new family of modular proteoglycans whose general supramolecular structure resembles that of hyalectans. However, neither their protein nor their glycan moieties have significant sequence homology to other proteoglycans, despite having protein subunits equivalent to link proteins and to proteoglycan monomer core proteins, and glycan subunits equivalent to hyaluronan and to the glycosaminoglycans of hyalectans. In some species, these molecular components are assembled into a structure with a circular core formed by the link protein- and hyaluronan-like subunits. Besides their involvement in cell adhesion, these sponge proteoglycans, for which we propose the term spongicans, participate in signal transduction processes and are suspected to play a role in sponge self-nonself recognition. Their in vivo roles and the mild methods used to purify large amounts of functionally active spongicans make them ideal models to study the functions and possible new applications of proteoglycans in biomedical research.

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“…Reactions can be fast, such as in Clathria prolifera , which responds to allografting in two to six hours [2,23], or comparatively slow, as in Callyspongia diffusa , which can take up to a week to react [2,10,20,24,25,26]. Processes that characterise graft rejection may include cellular necrosis of one or both graft partners [2,10,20,24,25], collagen deposition to form a physicochemical barrier between the apposing sponges [2,12,22,23,27,28,29], cellular migration to the point of contact [20,21,22,23,29,30], and phagocytic or cytotoxic reactions [22,24,25,26]. Qualitative and quantitative responses to grafts are replicable and predictable [2,24,31], between both first-party (sponge A:B replicates) and third-party (where A:B fusion predicts identical A:C and B:C reactions) grafts [13,25,28].…”

Section: Introductionmentioning

confidence: 99%

Transcriptomic Profiling of the Allorecognition Response to Grafting in the Demosponge Amphimedon queenslandica

Grice

Degnan

2017

Marine Drugs

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Sponges, despite their simple body plan, discriminate between self and nonself with remarkable specificity. Sponge grafting experiments simulate the effects of natural self or nonself contact under laboratory conditions. Here we take a transcriptomic approach to investigate the temporal response to self and nonself grafts in the marine demosponge Amphimedon queenslandica. Auto- and allografts were established, observed and sampled over a period of three days, over which time the grafts either rejected or accepted, depending on the identity of the paired individuals, in a replicable and predictable manner. Fourteen transcriptomes were generated that spanned the auto- and allograft responses. Self grafts fuse completely in under three days, and the process appears to be controlled by relatively few genes. In contrast, nonself grafting results in a complete lack of fusion after three days, and appears to involve a broad downregulation of normal biological processes, rather than the mounting of an intense defensive response.

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Chapter 4 Phenomena of Cellular Recognition in Sponges

Cited by 50 publications

References 28 publications

Accumulation in Marine Sponge Grafts of the mRNA Encoding the Main Proteins of the Cell Adhesion System

Accumulation in Marine Sponge Grafts of the mRNA Encoding the Main Proteins of the Cell Adhesion System

Circular proteoglycans from sponges: first members of the spongican family

Transcriptomic Profiling of the Allorecognition Response to Grafting in the Demosponge Amphimedon queenslandica

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