Variability of imposex development and reproductive alterations in the Patagonian gastropod Buccinanops globulosus inhabiting a polluted harbour area

El objetivo de este trabajo fue estudiar parámetros reproductivos y desarrollo de imposex en el caenogasterópodo Buccinanops globulosus que habita en una zona portuaria de alto tráfico marítimo y con presencia de contaminantes. Los resultados mostraron una mayor incidencia de imposex en hembras sin ovicápsulas que en hembras con ovicápsulas. Entre las hembras con imposex, el desarrollo del pene fue significativamente mayor en aquellas sin ovicápsulas (3.4 mm) que en las hembras con ovicápsulas (1,5 mm). En B. globulosus comúnmente un solo juvenil eclosiona por cada cápsula, sin embargo, en este estudio se registraron capsulas con múltiples embriones. Todos estos resultados sugieren una relación entre el desarrollo de imposex y alteraciones en los parámetros reproductivos de las hembras de B. globulosus que habitan en sitios con condiciones ambientales adversas (área contaminada).The aim of this work was to study the reproductive output and imposex parameters of the caenogastropod Buccinanops globulosus inhabiting a harbour area, with high maritime traffic and pollution. The results showed higher imposex incidence for non-gravid females than for gravid females (carrying egg capsules). Among imposex-affected females, mean penis size was significantly larger in non-gravid (3.4 mm) than gravid (1.5 mm) females. In B. globulosus usually a single juvenile hatches per egg capsule, but in this study capsules with multiple embryos were found. Overall, these results suggest a relationship between imposex development and alterations on the reproductive output of B. globulosus females living in adverse environmental conditions (polluted area).Fil: Primost, Monica Angelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; ArgentinaFil: Averbuj, Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; ArgentinaFil: Bigatti, Gregorio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentin

Contaminación costera y masculinización de caracoles marinos

El puerto de Mar del Plata, donde hace quince años se advirtió por primera vez en la costa atlántica de América del Sur, en caracoles de las especies Buccinanops monilifer y Adelomelon brasiliana, el fenómeno de impostación sexual, habitualmente llamado imposex en la literatura científica.Fil: Bigatti, Gregorio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Averbuj, Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Primost, Monica Angelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Giulianelli, Sebastian Jesus. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Penchaszadeh, Pablo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales ; Argentin

UV-R mitigation strategies in encapsulated embryos of the intertidal gastropod Acanthina monodon: A way to compensate for lack of parental care

Intracapsular embryonic development in the intertidal zone exposes embryos to various stress sources characteristic of this environment, including UV-R. They require defensive mechanisms to mitigate its adverse effects. The presence of total carotenoids (TC), and mycosporine-like amino acids (MAAs) was studied in adults, in encapsulated embryos, and in the egg capsule walls of the intertidal gastropod Acanthina monodon. Oxygen consumption rates (OCR) were determined in encapsulated and excapsulated embryos exposed to photosynthetically active radiation (PAR) and PAR + UV-A + UV-B to understand if the capsule wall is a protective structure for encapsulated embryos. The results showed the presence of TC in adult pedal and gonad tissues, and in all encapsulated stages. MAAs were not detected. The physical structure of the capsule wall retained most wavelengths, being particularly efficient in the UV-B range. Excapsulated embryos exposed to PAR + UV-A + UV-B radiation increased its OCR compared to encapsulated embryos, indicating the protective character of the capsule wall.Fil: Cubillos, Victor M.. Universidad Austral de Chile; ChileFil: Salas Yanquin, Luis P.. Universidad Austral de Chile; ChileFil: Buchner Miranda, Joseline. Universidad Austral de Chile; ChileFil: Ramirez, Felipe. Universidad Austral de Chile; ChileFil: Zabala, Maria Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; ArgentinaFil: Averbuj, Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; ArgentinaFil: Marquez, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina. Universidad Nacional de la Patagonia. Facultad de Ciencias Naturales. Sede Puerto Madryn; ArgentinaFil: Jaramillo, Hans. Universidad Austral de Chile; ChileFil: Chaparro, Oscar R.. Universidad Austral de Chile; Chil

Growing up in the deep-sea protected development in deep-sea invertebrates: A case study in the southwestern Atlantic Ocean

Marine invertebrates display a range of reproductive strategies, from external fertilization to several methods to protect the young. Both brooding or protected development of benthic species and direct development species (when juveniles born in a smaller version of its adult form) involves reducing the time that the larvae and/or juveniles spend in the plankton. The different forms of juvenile protection are often associated with the taxonomic group, although certain groups are much diversified in terms of their reproductive modes. However, the area where the species live also seems to play a key role. Several authors have indicated the unusual proportion of brooding species in the Southern Ocean, in particular in the southwestern Atlantic, including its adjacent deep-sea. The knowledge about the reproductive characteristics of most of the fauna in this area remains unknown. Proof of this are the great number of studies carried out in recent years, describing the reproductive features of several species (many also new), with some of them having many peculiarities about their biology.Fil: Teso, Silvia Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Martinez, Mariano Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Lauretta, Daniel Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Pastorino, Roberto Santiago Guido. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Urteaga, Diego Gaston. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Averbuj, Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; ArgentinaFil: Brogger, Martin Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; ArgentinaFil: Arrighetti, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Rivadeneira, Pamela Ruth. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Flores, Jonathan Nahuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Pertossi, Renata Micaela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Sánchez, Noelia Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Pacheco, Leonel Ivan. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Di Luca, Javier Agustín. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Sanchez Antelo, Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Risaro, Jessica Ayelen. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Ciocco, Rocio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Penchaszadeh, Pablo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentin

Schizophrenia-associated somatic copy-number variants from 12,834 cases reveal recurrent NRXN1 and ABCB11 disruptions

While germline copy-number variants (CNVs) contribute to schizophrenia (SCZ) risk, the contribution of somatic CNVs (sCNVs)—present in some but not all cells—remains unknown. We identified sCNVs using blood-derived genotype arrays from 12,834 SCZ cases and 11,648 controls, filtering sCNVs at loci recurrently mutated in clonal blood disorders. Likely early-developmental sCNVs were more common in cases (0.91%) than controls (0.51%, p = 2.68e−4), with recurrent somatic deletions of exons 1–5 of the NRXN1 gene in five SCZ cases. Hi-C maps revealed ectopic, allele-specific loops forming between a potential cryptic promoter and non-coding cis-regulatory elements upon 5′ deletions in NRXN1. We also observed recurrent intragenic deletions of ABCB11, encoding a transporter implicated in anti-psychotic response, in five treatment-resistant SCZ cases and showed that ABCB11 is specifically enriched in neurons forming mesocortical and mesolimbic dopaminergic projections. Our results indicate potential roles of sCNVs in SCZ risk

Sexual dimorphism in the shell of a nassariid gastropod. A 3D geometric morphometrics approach

Among gastropods, dimorphism is reported in shell size, radular characteristic, and to a lesser extent in shell shape. The relationship of dimorphic characters of the shell with spawning is scarcely studied in literature. Buccinanops globulosus is an interesting model to study sexual dimorphism in shell shape, because the adults attach their egg capsules to the females' own shells (callus zone). Our hypothesis is that the shell dimorphism is evidenced in the form (size and shape) of callus zones of the females' shells, compared with the males'. In order to test this hypothesis we use a 3D geometric morphometrics (GM) method with several advantages over 2D GM. The relationship between callus shape and size was allometric. During growth, the main callus shape changes are related to the mean size increment, which is more evident in larger females. These callus zones are characteristically slender in males and small females, and more inflated in large females. Our analyses revealed that female shells are different from male ones and those differences are significant on the callus zone where the egg capsules are attached by the female. This finding suggests a relationship of the shell form with spawning. Our findings are not only relevant in terms of the shell dimorphism of the particular spawning substrate area (callus zones) and its reproductive implications, but also provide insights into the evaluation of shell shape variation on areas without type I or II anatomical landmarks in 3D GM.Fil: Marquez, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; ArgentinaFil: Averbuj, Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentin

Reproductive biology in the South Western Atlantic genus Buccinanops (Nassariidae): the case of Buccinanops paytensis

The reproductive biology of the nassariid Buccinanops paytensis is considered and compared with the other species in the genus. In B. paytensis an average of 42 egg capsules were attached to the shell of each female. A mean of 2738 eggs (246 µm in diameter) occurred per capsule and generally only one embryo developed inside, measuring c. 5 mm in shell length when hatching; eggs at pre-hatching stage are still abundant. Four percent of the egg capsules contained two pre-hatching embryos of unequal size, in which nurse eggs were totally consumed. ‘Larval kidneys’ were recorded at advanced developmental stages (‘pediveliger’). Adaptations to reproduction in soft substrates involve a great amount of energy being invested by the females (nurse eggs and maternal care of the capsules), which enhance the survival of juveniles. Buccinanops paytensis had the highest number of nurse eggs per embryo (c. 2600), but B. cochlidium had more eggs and embryos per female (c. 3100 and c. 800, respectively). Hatching of crawling juveniles occurred in about 4 months in all species. When multiple embryos occur in an egg capsule, food becomes limiting, hatching size is reduced and unequal. Evidence of sibling cannibalism was observed in B. monilifer. Major differences are related to the spawn size, and the amount of nurse eggs and feeding modality of each species, which impact on the reproductive output (number and size of the juveniles) per female. The South African nassariid genus Bullia differs in egg capsule morphology and attachment, but is similar in having nurse eggs and direct development.Fil: Averbuj, Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; ArgentinaFil: Penchaszadeh, Pablo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentin

Reproductive seasonality, oviposition and development of the nassariid whelk Buccinanops cochlidium (Dillwyn, 1817) in Patagonia, Argentina

Seasonality of reproduction in Buccinanops cochlidium, including mating, oviposition and embryonic development, was studied within a population in Patagonia. Mating was observed mainly during autumn and winter (March to October). Females carrying egg capsules were found between July and October when water temperature was 10°C, while development of embryos continued until February (the hatching peak) when water temperature was 18°C. All egg capsule masses were found attached to the shells of females 80-102 mm in length. The spawn consisted of 80 to 238 egg capsules, attached to the apertural callus of the shell. Linear regression analysis showed no significant relationship between female size and number of egg capsules. Each egg capsule contained 3100 eggs on average, with a mean egg diameter before cleavage of 227.5 μm. One to 20 embryos completed their development within each egg capsule by ingesting around 570 nurse eggs. The embryos followed a typical holoblastic spiralian division until gastrulation. During the 'veliger' stage the embryo consumed nurse eggs and formed a large rounded embryo up to 2 mm in diameter. After shell development the embryos hatched as crawling juveniles of 4.0 mm shell length through an opening opposite to the capsule stalk. There was an inverse relationship between the mean hatching shell size and the number of embryos per egg capsule. Under laboratory conditions development was completed in four months.Fil: Averbuj, Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; ArgentinaFil: Penchaszadeh, Pablo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; Argentin

The genus Buccinanops: A Model for Eye Loss in Caenogastropods

The genus Buccinanops (d'Orbigny, 1841) (Caenogastropoda, Nassarriidae) is endemic to the SW Atlantic Ocean, and the name implies no eyes, due to the lack of visible eyes in adults. We recognize for the first time the occurrence of eyes during several developmental stages within Buccinanops. Eye spots in Buccinanops cochlidium (Dillwyn, 1817) were observed during intracapsular development and in hatchlings and juveniles. Eyes were histologically confirmed in embryonic cephalic tentacles; they were comprised of sensory cells, supportive cells, a lens, and an optic nerve cord. The ontogenetic history of the eyes of B. cochlidium is discussed.Fil: Averbuj, Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Penchaszadeh, Pablo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentin

Embryonic development, feeding and intracapsular oxygen availability in Trophon geversianus (Gastropoda: Muricidae)

Large-scale patterns of encapsulated embryo development and causal factors determining developmental success in the marine environment have been relevant issues of research for decades. We studied the embryonic development and intracapsular oxygen availability of Trophon geversianus in egg capsules from northern Patagonia (Golfo Nuevo, Argentina). The intracapsular embryonic development had a mean duration of 112 days (at 1214°C). The initial number of eggs per capsule was 197 (mean diameter 270 μm), but on average only four embryos per capsule reached the juvenile stage. Embryos fed on nurse eggs (which disintegrated spontaneously 48 h after oviposition). The sequence of intracapsular developmental stages was recorded from egg to hatching occurred at the crawling stage (mean shell length 2.8 mm). Maximum growth rate was observed at the 'veliger' stage, while nurse eggs were consumed. A decrease in embryo number was observed between prehatching and hatching. Cannibalism was recorded in an egg capsule containing a prehatching embryo, which showed signs of shell drilling by the accessory boring organ. Intracapsular oxygen availability decreased from 90 during the cleavage stage to 45 of air saturation in the final stages of development (at 13°C). Abnormal embryos were recognized in egg capsules, probably associated with food competition or oxygen limitation.Fil: Cumplido Esmoris, Mariano José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Pappalardo, Paula. Pontificia Universidad Católica de Chile; ChileFil: Fernández, Miriam. Pontificia Universidad Católica de Chile; ChileFil: Averbuj, Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Bigatti, Gregorio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentin