Full allogeneic fusion of embryos in a holothuroid echinoderm

Whole-body chimaeras (organisms composed of genetically distinct cells) have been directly observed in modular/colonial organisms (e.g. corals, sponges, ascidians); whereas in unitary deuterostosmes (including mammals) they have only been detected indirectly through molecular analysis. Here, we document for the first time the step-by-step development of whole-body chimaeras in the holothuroid Cucumaria frondosa , a unitary deuterostome belonging to the phylum Echinodermata. To the best of our knowledge, this is the most derived unitary metazoan in which direct investigation of zygote fusibility has been undertaken. Fusion occurred among hatched blastulae, never during earlier (unhatched) or later (larval) stages. The fully fused chimaeric propagules were two to five times larger than non-chimaeric embryos. Fusion was positively correlated with propagule density and facilitated by the natural tendency of early embryos to agglomerate. The discovery of natural chimaerism in a unitary deuterostome that possesses large externally fertilized eggs provides a framework to explore key aspects of evolutionary biology, histocompatibility and cell transplantation in biomedical research.

Download Full-text

Identification of vimentin and novel vimentin-related proteins in Xenopus oocytes and early embryos

Development ◽

10.1242/dev.110.4.1185 ◽

1990 ◽

Vol 110 (4) ◽

pp. 1185-1195

Author(s):

N.P. Torpey ◽

J. Heasman ◽

C.C. Wylie

Keyword(s):

Fusion Proteins ◽

Xenopus Oocytes ◽

Germ Plasm ◽

Radial Glial Cells ◽

Larval Stages ◽

Early Embryos ◽

Radial Glial ◽

Synthetic Mrna ◽

Related Proteins ◽

First Time

We have made antibodies against fusion proteins of Xenopus vimentin. We show for the first time the distribution of vimentin in larval stages, where it is found in cells of mesenchymal origin, and in radial glial cells. In sections of Xenopus oocytes and early embryos, immunocytochemistry reveals the presence of an extensive cytoplasmic network, distributed in an animal-vegetal gradient. Germ plasm stains particularly strongly. The form of the IF proteins in this network is unusual. In immunoblot experiments the anti-vimentin antibodies detect a number of distinct proteins. We have identified those that are the products of the two known vimentin genes, by injection of synthetic mRNA transcribed from cloned vimentin cDNAs into oocytes, followed by two-dimensional Western blotting. This has demonstrated unambiguously that one Xenopus vimentin, Vim1, is present in oocytes and early embryos. However, two other immunoreactive proteins detected in Triton extracts of oocytes and early embryos are not the products of Vim1, since depletion of vimentin mRNA by antisense oligonucleotide injection has no effect on the synthesis of these proteins. These results suggest that novel IF-like proteins are expressed in Xenopus oocytes and early embryos.

Download Full-text

Darwin's two competing phylogenetic trees: marsupials as ancestors or sister taxa?

Archives of Natural History ◽

10.3366/anh.2012.0091 ◽

2012 ◽

Vol 39 (2) ◽

pp. 217-233 ◽

Cited By ~ 4

Author(s):

J. David Archibald

Keyword(s):

Fossil Record ◽

Evolutionary Biology ◽

Phylogenetic Trees ◽

Charles Darwin ◽

The Other ◽

Charles Lyell ◽

Single Origin ◽

Molecular Studies ◽

Richard Owen ◽

First Time

Studies of the origin and diversification of major groups of plants and animals are contentious topics in current evolutionary biology. This includes the study of the timing and relationships of the two major clades of extant mammals – marsupials and placentals. Molecular studies concerned with marsupial and placental origin and diversification can be at odds with the fossil record. Such studies are, however, not a recent phenomenon. Over 150 years ago Charles Darwin weighed two alternative views on the origin of marsupials and placentals. Less than a year after the publication of On the origin of species, Darwin outlined these in a letter to Charles Lyell dated 23 September 1860. The letter concluded with two competing phylogenetic diagrams. One showed marsupials as ancestral to both living marsupials and placentals, whereas the other showed a non-marsupial, non-placental as being ancestral to both living marsupials and placentals. These two diagrams are published here for the first time. These are the only such competing phylogenetic diagrams that Darwin is known to have produced. In addition to examining the question of mammalian origins in this letter and in other manuscript notes discussed here, Darwin confronted the broader issue as to whether major groups of animals had a single origin (monophyly) or were the result of “continuous creation” as advocated for some groups by Richard Owen. Charles Lyell had held similar views to those of Owen, but it is clear from correspondence with Darwin that he was beginning to accept the idea of monophyly of major groups.

Download Full-text

Safety assessment of biological raw materials in the system of medicines quality assurance

10.33920/med-06-2002-05 ◽

2020 ◽

pp. 63-72

Author(s):

Yu. Olefir ◽

E. Sakanyan ◽

I. Osipova ◽

V. Dobrynin ◽

M. Smirnova ◽

...

Keyword(s):

Raw Materials ◽

State Level ◽

The State ◽

Spongiform Encephalopathy ◽

Safety Standards ◽

Wide Range ◽

The Russian Federation ◽

Key Aspects ◽

First Time ◽

Medicines Quality

The entry of a wide range of biotechnological products into the pharmaceutical market calls for rein-forcement of the quality, efficacy and safety standards at the state level. The following general monographs have been elaborated for the first time to be included into the State Pharmacopoeia of the Russian Federation, XIV edition: "Viral safety" and "Reduction of the risk of transmitting animal spongiform encephalopathy via medicinal products". These general monographs were elaborated taking into account the requirements of foreign pharmacopoeias and the WHO recommendations. The present paper summarises the key aspects of the monographs.

Download Full-text

Associations of Phoretic Mites on Bark Beetles of the Genus Ips in the Black Sea Mountains of Turkey

Forests ◽

10.3390/f12050516 ◽

2021 ◽

Vol 12 (5) ◽

pp. 516

Author(s):

Cihan Cilbircioğlu ◽

Marta Kovač ◽

Milan Pernek

Keyword(s):

Black Sea ◽

Bark Beetles ◽

Pinus Nigra ◽

Mite Species ◽

Tree Bark ◽

The Black Sea ◽

Forest Pests ◽

Larval Stages ◽

Suitable Habitats ◽

First Time

Phoretic mites use bark beetles for transportation to new, suitable habitats. Some phoretic mites act as predators and parasitoids of the bark beetles’ immature stages, especially egg and early larval stages, and are potential agents for the biological control of scolytine forest pests. Mites live very frequently in relationships with other invertebrates. Many are found in association with various species of bark beetles. Here, a total of 41 specimens of different bark beetles of the genus Ips (Ips acuminatus, Ips sexdentatus and Ips typographus) were studied for presence, species composition, and abundance of phoretic mites. The beetles were collected on dead wood and parts of tree bark of Pinus nigra, Pinus sylvestris and Picea abies in the Black Sea Mountains in Kastamonu and Artin Province of Turkey. A total of nine mite species were found, including Dendrolaelaps quadrisetus, Ereynetes sp., Histiostoma piceae, Paraleius cf. leontonychus, Pleuronectocelaeno barbara., Proctolaelaps hystricoides, Schizostethus simulatrix, Trichouropoda lamellosa and Uroobovellaipidis. All species are identified for the first time within Turkish fauna.

Download Full-text

Franciscan Books and their Readers

10.5117/9789463729512 ◽

2022 ◽

Author(s):

René Hernández

Keyword(s):

Space Form ◽

Northern Italy ◽

Ideal Space ◽

Skilled Readers ◽

Personal Library ◽

Key Aspects ◽

Cultural Agency ◽

First Time ◽

The Ideal

The book explores the manuscripts written, read, and studied by Franciscan friars from the thirteenth to the fifteenth centuries in Northern Italy, and specifically Padua, assessing four key aspects: ideal, space, form and readership. The ideal is studied through the regulations that determined what manuscripts should aim for. Space refers to the development and role of Franciscan libraries. The form is revealed by the assessment of the physical configuration of a set of representative manuscripts read, written, and manufactured by the friars. Finally, the study of the readership shows how Franciscans were skilled readers who employed certain forms of the manuscript as a portable, personal library, and as a tool for learning and pastoral care. By comparing the book collections of Padua’s reformed and unreformed medieval Franciscan libraries for the first time, this study reveals new features of the ground-breaking cultural agency of medieval friars.

Download Full-text

Microfluidic-based imaging of complete C. elegans larval development

10.1101/2021.03.31.437890 ◽

2021 ◽

Author(s):

Simon Berger ◽

Silvan Spiri ◽

Andrew deMello ◽

Alex Hajnal

Keyword(s):

Imaging Method ◽

Cover Glass ◽

Vulval Development ◽

C Elegans ◽

Larval Stages ◽

Seam Cell ◽

Time Observation ◽

On Chip ◽

First Time

Several microfluidic-based methods for long-term C. elegans imaging have been introduced in recent years, allowing real-time observation of previously inaccessible processes. The ex-isting methods either permit imaging across multiple larval stages without maintaining a stable worm orientation, or allow for very good immobilization but are only suitable for shorter experiments. Here, we present a novel microfluidic imaging method, which allows parallel live-imaging across multiple larval stages, while delivering excellent immobilization and maintaining worm orientation and identity over time. This is achieved by employing an array of microfluidic trap channels carefully tuned to maintain worms in a stable orienta-tion, while allowing growth and molting to occur. Immobilization is supported by an active hydraulic valve, which presses worms onto the cover glass during image acquisition, with the animals remaining free for most of an experiment. Excellent quality images can be ac-quired of multiple worms in parallel, with little impact of the imaging method on worm via-bility or developmental timing. The capabilities of this methodology are demonstrated by observing the hypodermal seam cell divisions and, for the first time, the entire process of vulval development from induction to the end of morphogenesis. Moreover, we demonstrate RNAi on-chip, which allows for perturbation of dynamic developmental processes, such as basement membrane breaching during anchor cell invasion.

Download Full-text

PPA1 Regulates Systemic Insulin Sensitivity by Maintaining Adipocyte Mitochondria Function as a Novel PPARγ Target Gene

10.2337/figshare.14135777.v1 ◽

2021 ◽

Author(s):

Ye Yin ◽

Yangyang Wu ◽

Xu Zhang ◽

Yeting Zhu ◽

Yue Sun ◽

...

Keyword(s):

Adipose Tissue ◽

Mitochondrial Function ◽

Metabolic Disorders ◽

Target Gene ◽

Fat Body ◽

Whole Body ◽

Inorganic Pyrophosphatase ◽

Severe Insulin Resistance ◽

Adipose Tissue Development ◽

First Time

<a>Downregulation of mitochondrial function in adipose tissue is considered as one important driver for the development of obesity-associated metabolic disorders. Inorganic Pyrophosphatase 1 (PPA1) is an enzyme catalyzes the hydrolysis of PPi to Pi, and is required for anabolism to take place in cells. Although alternation of PPA1 has been related to some diseases, the importance of PPA1 in metabolic syndromes has never been discussed before. In this study, we found that global PPA1 knockout mice (PPA1+/-) showed impaired glucose tolerance and severe insulin resistance under HFD feeding. In addition, impaired adipose tissue development and ectopic lipid accumulation were also observed. Conversely, overexpression of PPA1 in adipose tissue by AAV injection can partly reverse the metabolic disorders in PPA1+/- mice, suggesting that impaired adipose tissue function is responsible for the metabolic disorders observed in PPA1+/- mice. Mechanistic studies revealed that PPA1 acted as a PPARγ target gene to maintain mitochondrial function in adipocytes. Furthermore, specific knockdown of PPA1 in fat body of Drosophila led to impaired mitochondria morphology, decreased lipid storage, and made Drosophila more sensitive to starvation. In conclusion, for the first time, our findings demonstrated the importance of PPA1 in maintaining adipose tissue function and whole body metabolic homeostasis.</a>

Download Full-text

Mutator Foci Are Regulated by Developmental Stage, RNA, and the Germline Cell Cycle in Caenorhabditis elegans

G3 Genes|Genome|Genetics ◽

10.1534/g3.120.401514 ◽

2020 ◽

Vol 10 (10) ◽

pp. 3719-3728 ◽

Cited By ~ 1

Author(s):

Celja J. Uebel ◽

Dana Agbede ◽

Dylan C. Wallis ◽

Carolyn M. Phillips

Keyword(s):

Cell Cycle ◽

Caenorhabditis Elegans ◽

Epigenetic Inheritance ◽

Germline Cell ◽

Late Pachytene ◽

Larval Stages ◽

Transcriptional Inhibition ◽

Male Germline ◽

Early Embryos ◽

Adult Hermaphrodite

RNA interference is a crucial gene regulatory mechanism in Caenorhabditis elegans. Phase-separated perinuclear germline compartments called Mutator foci are a key element of RNAi, ensuring robust gene silencing and transgenerational epigenetic inheritance. Despite their importance, Mutator foci regulation is not well understood, and observations of Mutator foci have been largely limited to adult hermaphrodite germlines. Here we reveal that punctate Mutator foci arise in the progenitor germ cells of early embryos and persist throughout all larval stages. They are additionally present throughout the male germline and in the cytoplasm of post-meiotic spermatids, suggestive of a role in paternal epigenetic inheritance. In the adult germline, transcriptional inhibition results in a pachytene-specific loss of Mutator foci, indicating that Mutator foci are partially reliant on RNA for their stability. Finally, we demonstrate that Mutator foci intensity is modulated by the stage of the germline cell cycle and specifically, that Mutator foci are brightest and most robust in the mitotic cells, transition zone, and late pachytene of adult germlines. Thus, our data defines several new factors that modulate Mutator foci morphology which may ultimately have implications for efficacy of RNAi in certain cell stages or environments.

Download Full-text

Associations of Phoretic Mites on Bark Beetles of the Genus Ips in the Black Sea Mountains of Turkey

10.20944/preprints202101.0285.v1 ◽

2021 ◽

Author(s):

Cihan Cilbircioğlu ◽

Marta Matek Kovač ◽

Milan Pernek

Keyword(s):

Black Sea ◽

Bark Beetles ◽

Pinus Nigra ◽

Mite Species ◽

Tree Bark ◽

The Black Sea ◽

Forest Pests ◽

Larval Stages ◽

Suitable Habitats ◽

First Time

Phoretic mites use bark beetles for transportation to new, suitable habitats. Some phoretic mites act as predators and parasitoids of the bark beetles’ immature stages, especially egg and early larval stages, and are potential agents for the biological control of scolytine forest pests. One of the most numerous and largest mite orders is Mesostigmata which live very frequently in relationships with other invertebrates. Many are found in association with various species of bark beetles. Here, a total of 41 specimens of different bark beetles of the genus Ips (I. acuminatus, I. sexdentatus and I. typographus) were studied for presence, species composition, and abundance of phoretic mites. The beetles were collected on dead wood and parts of tree bark of Pinus nigra, P. slyvestris and Picea abies in the Black Sea Mountains in Kastamonu and Artin Province of Turkey. A total of 9 mite species in 2 genera were found, including Dendrolaelaps quadrisetus, Ereynetes sp., Histiostoma piceae, Paraleius cf. leontonychus, Pleuronectocaeleno barbara., Proctolaelaps hystricoides, Schizostethus simulatrix, Trichouropoda lamellosa and Urobovella ipidis. All species and genera are identified for the first time within Turkish fauna.

Download Full-text

Neural network detected in a presumed vestigial trait: ultrastructure of the salmonid adipose fin

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2011.1009 ◽

2011 ◽

Vol 279 (1728) ◽

pp. 553-563 ◽

Cited By ~ 33

Author(s):

J. A. Buckland-Nicks ◽

M. Gillis ◽

T. E. Reimchen

Keyword(s):

Evolutionary Biology ◽

Primary Cilia ◽

Free Edge ◽

Energetic Cost ◽

Developmental Constraints ◽

Fisheries Science ◽

Adipose Fin ◽

First Time ◽

Two Sides ◽

Turbulent Water

A wide variety of rudimentary and apparently non-functional traits have persisted over extended evolutionary time. Recent evidence has shown that some of these traits may be maintained as a result of developmental constraints or neutral energetic cost, but for others their true function was not recognized. The adipose fin is small, fleshy, non-rayed and located between the dorsal and caudal fins on eight orders of basal teleosts and has traditionally been regarded as vestigial without clear function. We describe here the ultrastructure of the adipose fin and for the first time, to our knowledge, present evidence of extensive nervous tissue, as well as an unusual subdermal complex of interconnected astrocyte-like cells equipped with primary cilia. The fin contains neither adipose tissue nor fin rays. Many fusiform actinotrichia, comprising dense striated macrofibrils, support the free edge and connect with collagen cables that link the two sides. These results are consistent with a recent hypothesis that the adipose fin may act as a precaudal flow sensor, where its removal can be detrimental to swimming efficiency in turbulent water. Our findings provide insight to the broader themes of function versus constraints in evolutionary biology and may have significance for fisheries science, as the adipose fin is routinely removed from millions of salmonids each year.

Download Full-text