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Willie J Swanson - One of the best experts on this subject based on the ideXlab platform.
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duplicate abalone Egg coat Proteins bind sperm lysin similarly but evolve oppositely consistent with molecular mimicry at fertilization
PLOS Genetics, 2013Co-Authors: Jan E Aagaard, Stevan A Springer, Scott D Soelberg, Willie J SwansonAbstract:Sperm and Egg Proteins constitute a remarkable paradigm in evolutionary biology: despite their fundamental role in mediating fertilization (suggesting stasis), some of these molecules are among the most rapidly evolving ones known, and their divergence can lead to reproductive isolation. Because of strong selection to maintain function among interbreeding individuals, interacting fertilization Proteins should also exhibit a strong signal of correlated divergence among closely related species. We use evidence of such molecular co-evolution to target biochemical studies of fertilization in North Pacific abalone (Haliotis spp.), a model system of reproductive protein evolution. We test the evolutionary rates (dN/dS) of abalone sperm lysin and two duplicated Egg coat Proteins (VERL and VEZP14), and find a signal of co-evolution specific to ZP-N, a putative sperm binding motif previously identified by homology modeling. Positively selected residues in VERL and VEZP14 occur on the same face of the structural model, suggesting a common mode of interaction with sperm lysin. We test this computational prediction biochemically, confirming that the ZP-N motif is sufficient to bind lysin and that the affinities of VERL and VEZP14 are comparable. However, we also find that on phylogenetic lineages where lysin and VERL evolve rapidly, VEZP14 evolves slowly, and vice versa. We describe a model of sexual conflict that can recreate this pattern of anti-correlated evolution by assuming that VEZP14 acts as a VERL mimic, reducing the intensity of sexual conflict and slowing the co-evolution of lysin and VERL.
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zp domain Proteins in the abalone Egg coat include a paralog of verl under positive selection that binds lysin and 18 kda sperm Proteins
Molecular Biology and Evolution, 2010Co-Authors: Jan E Aagaard, Victor D Vacquier, Michael J Maccoss, Willie J SwansonAbstract:Identifying fertilization molecules is key to our understanding of reproductive biology, yet only a few examples of interacting sperm and Egg Proteins are known. One of the best characterized comes from the invertebrate archeogastropod abalone (Haliotis spp.), where sperm lysin mediates passage through the protective Egg vitelline envelope (VE) by binding to the VE protein vitelline envelope receptor for lysin (VERL). Rapid adaptive divergence of abalone lysin and VERL are an example of positive selection on interacting fertilization Proteins contributing to reproductive isolation. Previously, we characterized a subset of the abalone VE Proteins that share a structural feature, the zona pellucida (ZP) domain, which is common to VERL and the Egg envelopes of vertebrates. Here, we use additional expressed sequence tag sequencing and shotgun proteomics to characterize this family of Proteins in the abalone Egg VE. We expand 3-fold the number of known ZP domain Proteins present within the VE (now 30 in total) and identify a paralog of VERL (vitelline envelope zona pellucida domain protein [VEZP] 14) that contains a putative lysin-binding motif. We find that, like VERL, the divergence of VEZP14 among abalone species is driven by positive selection on the lysin-binding motif alone and that these paralogous Egg VE Proteins bind a similar set of sperm Proteins including a rapidly evolving 18-kDa paralog of lysin, which may mediate sperm-Egg fusion. This work identifies an Egg coat paralog of VERL under positive selection and the candidate sperm Proteins with which it may interact during abalone fertilization.
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positive selection in the Egg receptor for abalone sperm lysin
Proceedings of the National Academy of Sciences of the United States of America, 2003Co-Authors: Blanca E Galindo, Victor D Vacquier, Willie J SwansonAbstract:The mechanism of speciation is a central problem in evolutionary biology. In free-spawning animals with no complex mating behavior, prezygotic reproductive isolation (speciation) could result from the rapid divergence of genes coding for sperm and Egg Proteins that bind each other during fertilization. In abalone, sperm lysin evolves rapidly by positive Darwinian selection. The Egg vitelline envelope receptor for lysin had previously been shown to evolve neutrally and be subjected to concerted evolution. Several mathematical simulations predict that both male and female reproductive Proteins should evolve rapidly by positive selection. Here we report that the sequence diversity of the amino-terminal end of the Egg vitelline envelope receptor for lysin has been promoted by positive Darwinian selection. These data provide molecular support for theoretical models showing that the two sexes are locked in a “coevolutionary chase” that could be driven by processes such as sexual selection, sexual conflict, or microbial attack (pathogen avoidance). The result of this continuous coevolution of the gamete recognition system could be the splitting of one population into two that are reproductively isolated (speciation).
Horacio Heras - One of the best experts on this subject based on the ideXlab platform.
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Agglutinating Activity and Structural Characterization of Scalarin, the Major Egg Protein of the Snail Pomacea scalaris (d’Orbigny, 1832)
2016Co-Authors: Santiago Ituarte, Marcos Sebastián Dreon, Marcelo Ceolin, Horacio HerasAbstract:Apple snail perivitellins are emerging as ecologically important reproductive Proteins. To elucidate if the protective functions of the Egg Proteins of Pomacea canaliculata (Caenogastropoda, Ampullariidae), involved in embryo defenses, are present in other Pomacea species we studied scalarin (PsSC), the major perivitellin of Pomacea scalaris. Using small angle X-ray scattering, fluorescence and absorption spectroscopy and biochemical methods, we analyzed PsSC structural stability, agglutinating activity, sugar specificity and protease resistance. PsSC aggluttinated rabbit, and, to a lesser extent, human B and A erythrocytes independently of divalent metals Ca2+ and Mg2+ were strongly inhibited by galactosamine and glucosamine. The protein was structurally stable between pH 2.0 to 10.0, though agglutination occurred only between pH 4.0 to 8.0 (maximum activity at pH 7.0). The agglutinating activity was conserved up to 60uC and completely lost above 80uC, in agreement with the structural thermal stability of the protein (up to 60uC). PsSC was able to withstand in vitro gastrointestinal digestion, and showed no trypsin inhibition activity. The presence of lectin activity has been reported in Eggs of other Pomacea snails, but here we link for the first time, this activity to an apple snail multifunctional perivitellin
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the major Egg reserve protein from the invasive apple snail pomacea maculata is a complex carotenoprotein related to those of pomacea canaliculata and pomacea scalaris
Comparative Biochemistry and Physiology B, 2014Co-Authors: Maria Yanina Pasquevich, Marcos Sebastián Dreon, Horacio HerasAbstract:Snails from the genus Pomacea lay conspicuous masses of brightly colored Eggs above the water. Coloration is given by carotenoProteins that also which play important roles in protection against sun radiation, stabilizing and transporting antioxidant molecules and helping to protect embryos from desiccation and predators. They seem a key acquisition, but have been little studied. Here we report the characteristics of the major carotenoprotein from Pomacea maculata and the first comparison among these Egg Proteins. This particle, hereafter PmPV1, represents ~52% of perivitellin fluid protein. It is a glyco-lipo-carotenoprotein responsible for the bright reddish Egg coloration. With VHDL characteristics, PmPV1 apparent molecular mass is 294kDa, composed of five non-covalently bound subunits of pI 4.7-9.8 and masses between 26 and 36kDa whose N-terminal sequences were obtained. It is a glyco-lipo-carotenoprotein scarcely lipidated (<1%) but highly glycosilated (13% by wt). Lipids include phospholipids, free fatty acids and carotenoids; mannose and galactose predominate over other monosaccharides. Main carotenoids are esterified and non-esterified astaxanthin (71 and 25%, respectively). Carotenoid removal does not seem to affect the structural characteristics of the oligomer, while deglycosilation reduces subunit number from five to a single one. The carotenoid-protein association protected the former against oxidation. PmPV1 cross reacts with polyclonal antibodies against the PcOvo, the major carotenoprotein from Pomacea canaliculata. The characterization of PmPV1 allows the first comparisons among snail carotenoProteins and further highlights the importance of these perivitellins in the reproductive strategy of Pomacea.
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structure and stability of the neurotoxin pv2 from the Eggs of the apple snail pomacea canaliculata
Biochimica et Biophysica Acta, 2010Co-Authors: Maria Victoria Frassa, Marcelo Ceolin, Marcos Sebastián Dreon, Horacio HerasAbstract:There is little information on the Egg Proteins of gastropod mollusks. Here we focus on PV2, a novel neurotoxin from snail Eggs, studying its size, shape, structure, and stability, using small angle X-ray scattering (SAXS), absorption and fluorescence spectroscopy, circular dichroism, electron microscopy and partial proteolysis. Results indicate that PV2 is a compact and well folded oligomer of 130x44 A. It is an octamer of four 98 kDa heterodimers composed of 67 and 31 kDa subunits. Subunits are held together by disulfide bonds. Dimers are assembled into native PV2 by non-covalent forces. The larger subunit is more susceptible to proteolysis, indicating it is less compactly folded and/or more exposed. Quenching of tryptophan fluorescence showed a single class of tryptophyl side chains occluded in hydrophobic regions. Native structure shows loss of secondary structure (alpha+beta) at 6 M urea or 60-70 degrees C; the effects on the quaternary structure suggest an unfolding without disassembling of the protein. The 3D model of PV2 presented here is the first for an Egg proteinaceous neurotoxin in animals.
Kwangsik Choi - One of the best experts on this subject based on the ideXlab platform.
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Purification and Characterization of Vitellin from the Egg of the Suminoe Oyster Crassostrea ariakensis and Cross-Reactivity of Anti-vitellin Antibody with Other Marine Invertebrate Egg Proteins.
The protein journal, 2017Co-Authors: Mausumi Adhya, Bong-kyu Kim, Hee-do Jeung, Moonjae Cho, Kwangsik ChoiAbstract:A polyclonal antibody specific to an Egg protein of Suminoe oyster Crassostrea ariakensis was previously developed in our laboratory to assess the reproductive life cycle of the oyster. The present study was undertaken to investigate vitellin of C. ariakensis (CAVt). Vitellin is an essential component of Egg Proteins in marine invertebrates as it provides energy and nutrients to the embryo and larvae. CAVt was purified from Eggs of the oyster using ammonium sulfate precipitation followed by affinity chromatography with Concanavalin A-agarose. Native polyacrylamide gel electrophoresis (PAGE) and sodium dodecyl sulfate PAGE showed that CAVt is a high molecular weight [532 kiloDaltons (kDa)] protein, with multiple subunits. Similar to other vitellin Proteins, it is a phospholipoglycoprotein composed of phospholipids (12.06%), carbohydrates (mannose, 10.08% or glucose, 9.84%), and alkali-labile phosphates (4.16%). Affinity chromatography, enzyme-linked immunosorbent aasay (ELISA) and western blot analysis revealed that CAVt is only present in the ovary, and two subunits of CAVt (72 and 35 kDa) are believed to be incorporated from the hemolymph into the oocyte. The antibody specific to CAVt (anti-CAVt), raised in rabbit, strongly cross reacted with the Egg Proteins of oyster species and scallops, suggesting that the antigenic epitopes are highly conserved among species. Our results suggest that the anti-CAVt antibody can be used to develop a tool similar to ELISA or western blotting for investigation of the effect of microorganisms on reproduction as well as the effect of chemicals on the endocrine system in C. ariakensis.
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development of a saxidomus purpuratus mollusca bivalvia Egg specific antibody for the quantification of Eggs using an enzyme linked immunosorbent assay
Journal of Shellfish Research, 2009Co-Authors: Kyungil Park, Jinwoo Choi, Kwangsik ChoiAbstract:Abstract We developed a polyclonal antibody from Egg Proteins of the butter clam, Saxidomus purpuratus, to quantify Eggs using an enzyme-linked immunosorbent assay (ELISA). SDS-PAGE showed that the Egg protein was composed of several peptides with molecular weights of 247, 200, 99, 91, 54 and 47 kDa. An immunoblotting assay indicated that the Egg-specific antibodies were developed from the 200 and 99 kDa peptides. The rabbit anticlam Egg IgG was able to detect as little as 0.078 μg/mL of S. purpuratus Egg protein by ELISA. A weight-normalized gonadosomatic index (GSI, mg dry Egg/mg dry tissue) was determined to follow the monthly changes in Egg production of the clams. Clam-Egg protein could be detected by ELISA during the entire sampling period (December to July), and GSI ranged from 0.035 (December) to 0.156 (February). The fecundity of the clams was measured from two spawning peaks in February and May and was estimated to be 22.6 million Eggs (GSI of 0.16) in February and 16 million Eggs in May (GSI of...
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application of enzyme linked immunosorbent assay for studying of reproduction in the manila clam ruditapes philippinarum mollusca bivalvia i quantifying Eggs
Aquaculture, 2004Co-Authors: Kyungil Park, Kwangsik ChoiAbstract:A polyclonal antibody specific to Ruditapes philippinarum Egg protein (ME-ab) was developed to quantify clam Eggs using an enzyme-linked immunosorbent assay (ELISA). Western blots revealed that ME-ab reacted with Egg Proteins of molecular masses 475, 84, and 40 kDa under nonreducing conditions and 330, 96, 64, 50, and 31 kDa under reducing conditions. With ELISA, ME-ab detected between 0.23 and 15 A gm l 1 of clam Egg protein; the number of Eggs per clam was quantified by dividing the weight of the total Egg protein by the average weight per Egg. Reproductive output, expressed as the gonadosomatic index (GSI), was calculated as the ratio of the Egg weight to the total tissue weight. Seasonal changes in reproductive output were measured in clams collected on a monthly basis from Gomso Bay, Korea. Clam Egg protein was detected during all months except January. The monthly mean GSI varied from 0 (January) to 0.25 (August), and the highest GSI (0.389) was recorded from a clam collected in late July. ELISA indicated that clams in Gomso Bay spawned when the gonad accounted for 20% of the total tissue weight. The fecundity estimated from individual clams before spawning ranged from 0.94 to 11.79 million Eggs, with a mean of 4.15 million. In conclusion, the ELISA used in this study was a sensitive and rapid method
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quantification of reproductive output of the butter clam saxidomus purpuratus sowerby 1852 using enzyme linked immunosorbent assay elisa
Ocean and Polar Research, 2003Co-Authors: Kyungil Park, Jinwoo Choi, Kwangsik ChoiAbstract:An immunological method was developed in this study to quantify reproductive output of the female butter clam, Saxidomus purpuratus. A clam Egg-specific polyclonal antibody was developed using the purified butter clam Egg as an antigen. An indirect Enzyme-Linked Immunosorbent Assay (ELISA) was used in quantitative measurement of the Eggs. Size of the butter clam Eggs ranged from in histology or in intact Eggs. The predominant Egg constituent was protein (37.44%), followed by lipids (11.40%) and carbohydrates (9.68%). The SDS-PAGE showed that the Egg Proteins are composed of several peptides of molecular weights consisting of 247, 200, 99, 91, 54 and 47 kDa. ELISA indicated that the clams collected from Geoje Island in May 2002 produced 8.2 to 26.8% of their body weight as Eggs or 9,307,309 to 31,156,333 with a mean of 16,931,893 Eggs per individual clam. The results of this study thus suggest that indirect ELISA using rabbit anti-clam Egg IgG as a primary antibody is a rapid, affordable and sensitive method to assess reproductive output of 5. purpuratus and possibly other bivalves using a small amount of Eggs.
Marcos Sebastián Dreon - One of the best experts on this subject based on the ideXlab platform.
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Agglutinating Activity and Structural Characterization of Scalarin, the Major Egg Protein of the Snail Pomacea scalaris (d’Orbigny, 1832)
2016Co-Authors: Santiago Ituarte, Marcos Sebastián Dreon, Marcelo Ceolin, Horacio HerasAbstract:Apple snail perivitellins are emerging as ecologically important reproductive Proteins. To elucidate if the protective functions of the Egg Proteins of Pomacea canaliculata (Caenogastropoda, Ampullariidae), involved in embryo defenses, are present in other Pomacea species we studied scalarin (PsSC), the major perivitellin of Pomacea scalaris. Using small angle X-ray scattering, fluorescence and absorption spectroscopy and biochemical methods, we analyzed PsSC structural stability, agglutinating activity, sugar specificity and protease resistance. PsSC aggluttinated rabbit, and, to a lesser extent, human B and A erythrocytes independently of divalent metals Ca2+ and Mg2+ were strongly inhibited by galactosamine and glucosamine. The protein was structurally stable between pH 2.0 to 10.0, though agglutination occurred only between pH 4.0 to 8.0 (maximum activity at pH 7.0). The agglutinating activity was conserved up to 60uC and completely lost above 80uC, in agreement with the structural thermal stability of the protein (up to 60uC). PsSC was able to withstand in vitro gastrointestinal digestion, and showed no trypsin inhibition activity. The presence of lectin activity has been reported in Eggs of other Pomacea snails, but here we link for the first time, this activity to an apple snail multifunctional perivitellin
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the major Egg reserve protein from the invasive apple snail pomacea maculata is a complex carotenoprotein related to those of pomacea canaliculata and pomacea scalaris
Comparative Biochemistry and Physiology B, 2014Co-Authors: Maria Yanina Pasquevich, Marcos Sebastián Dreon, Horacio HerasAbstract:Snails from the genus Pomacea lay conspicuous masses of brightly colored Eggs above the water. Coloration is given by carotenoProteins that also which play important roles in protection against sun radiation, stabilizing and transporting antioxidant molecules and helping to protect embryos from desiccation and predators. They seem a key acquisition, but have been little studied. Here we report the characteristics of the major carotenoprotein from Pomacea maculata and the first comparison among these Egg Proteins. This particle, hereafter PmPV1, represents ~52% of perivitellin fluid protein. It is a glyco-lipo-carotenoprotein responsible for the bright reddish Egg coloration. With VHDL characteristics, PmPV1 apparent molecular mass is 294kDa, composed of five non-covalently bound subunits of pI 4.7-9.8 and masses between 26 and 36kDa whose N-terminal sequences were obtained. It is a glyco-lipo-carotenoprotein scarcely lipidated (<1%) but highly glycosilated (13% by wt). Lipids include phospholipids, free fatty acids and carotenoids; mannose and galactose predominate over other monosaccharides. Main carotenoids are esterified and non-esterified astaxanthin (71 and 25%, respectively). Carotenoid removal does not seem to affect the structural characteristics of the oligomer, while deglycosilation reduces subunit number from five to a single one. The carotenoid-protein association protected the former against oxidation. PmPV1 cross reacts with polyclonal antibodies against the PcOvo, the major carotenoprotein from Pomacea canaliculata. The characterization of PmPV1 allows the first comparisons among snail carotenoProteins and further highlights the importance of these perivitellins in the reproductive strategy of Pomacea.
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structure and stability of the neurotoxin pv2 from the Eggs of the apple snail pomacea canaliculata
Biochimica et Biophysica Acta, 2010Co-Authors: Maria Victoria Frassa, Marcelo Ceolin, Marcos Sebastián Dreon, Horacio HerasAbstract:There is little information on the Egg Proteins of gastropod mollusks. Here we focus on PV2, a novel neurotoxin from snail Eggs, studying its size, shape, structure, and stability, using small angle X-ray scattering (SAXS), absorption and fluorescence spectroscopy, circular dichroism, electron microscopy and partial proteolysis. Results indicate that PV2 is a compact and well folded oligomer of 130x44 A. It is an octamer of four 98 kDa heterodimers composed of 67 and 31 kDa subunits. Subunits are held together by disulfide bonds. Dimers are assembled into native PV2 by non-covalent forces. The larger subunit is more susceptible to proteolysis, indicating it is less compactly folded and/or more exposed. Quenching of tryptophan fluorescence showed a single class of tryptophyl side chains occluded in hydrophobic regions. Native structure shows loss of secondary structure (alpha+beta) at 6 M urea or 60-70 degrees C; the effects on the quaternary structure suggest an unfolding without disassembling of the protein. The 3D model of PV2 presented here is the first for an Egg proteinaceous neurotoxin in animals.
Jan E Aagaard - One of the best experts on this subject based on the ideXlab platform.
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duplicate abalone Egg coat Proteins bind sperm lysin similarly but evolve oppositely consistent with molecular mimicry at fertilization
PLOS Genetics, 2013Co-Authors: Jan E Aagaard, Stevan A Springer, Scott D Soelberg, Willie J SwansonAbstract:Sperm and Egg Proteins constitute a remarkable paradigm in evolutionary biology: despite their fundamental role in mediating fertilization (suggesting stasis), some of these molecules are among the most rapidly evolving ones known, and their divergence can lead to reproductive isolation. Because of strong selection to maintain function among interbreeding individuals, interacting fertilization Proteins should also exhibit a strong signal of correlated divergence among closely related species. We use evidence of such molecular co-evolution to target biochemical studies of fertilization in North Pacific abalone (Haliotis spp.), a model system of reproductive protein evolution. We test the evolutionary rates (dN/dS) of abalone sperm lysin and two duplicated Egg coat Proteins (VERL and VEZP14), and find a signal of co-evolution specific to ZP-N, a putative sperm binding motif previously identified by homology modeling. Positively selected residues in VERL and VEZP14 occur on the same face of the structural model, suggesting a common mode of interaction with sperm lysin. We test this computational prediction biochemically, confirming that the ZP-N motif is sufficient to bind lysin and that the affinities of VERL and VEZP14 are comparable. However, we also find that on phylogenetic lineages where lysin and VERL evolve rapidly, VEZP14 evolves slowly, and vice versa. We describe a model of sexual conflict that can recreate this pattern of anti-correlated evolution by assuming that VEZP14 acts as a VERL mimic, reducing the intensity of sexual conflict and slowing the co-evolution of lysin and VERL.
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zp domain Proteins in the abalone Egg coat include a paralog of verl under positive selection that binds lysin and 18 kda sperm Proteins
Molecular Biology and Evolution, 2010Co-Authors: Jan E Aagaard, Victor D Vacquier, Michael J Maccoss, Willie J SwansonAbstract:Identifying fertilization molecules is key to our understanding of reproductive biology, yet only a few examples of interacting sperm and Egg Proteins are known. One of the best characterized comes from the invertebrate archeogastropod abalone (Haliotis spp.), where sperm lysin mediates passage through the protective Egg vitelline envelope (VE) by binding to the VE protein vitelline envelope receptor for lysin (VERL). Rapid adaptive divergence of abalone lysin and VERL are an example of positive selection on interacting fertilization Proteins contributing to reproductive isolation. Previously, we characterized a subset of the abalone VE Proteins that share a structural feature, the zona pellucida (ZP) domain, which is common to VERL and the Egg envelopes of vertebrates. Here, we use additional expressed sequence tag sequencing and shotgun proteomics to characterize this family of Proteins in the abalone Egg VE. We expand 3-fold the number of known ZP domain Proteins present within the VE (now 30 in total) and identify a paralog of VERL (vitelline envelope zona pellucida domain protein [VEZP] 14) that contains a putative lysin-binding motif. We find that, like VERL, the divergence of VEZP14 among abalone species is driven by positive selection on the lysin-binding motif alone and that these paralogous Egg VE Proteins bind a similar set of sperm Proteins including a rapidly evolving 18-kDa paralog of lysin, which may mediate sperm-Egg fusion. This work identifies an Egg coat paralog of VERL under positive selection and the candidate sperm Proteins with which it may interact during abalone fertilization.