A multiple comparative study of putative endosymbionts in three coexisting apple snail species

We here compare morphological and molecular characters of some putative endosymbiotic elements of the digestive gland of three ampullariid species (Pomacea canaliculata, Pomacea scalaris and Asolene platae) which coexist in Lake Regatas (Palermo, Buenos Aires). The putative endosymbionts were reported in these species and were identified as C and K corpuscles. The three species show tubuloacinar glands, each adenomere was constituted mainly by two distinct cell types (columnar and pyramidal). C and K corpuscles together occupied from one-fourth to one-fifth of the tissue area in the three host species, where C corpuscles were round and greenish-brown, were delimited by a distinct wall, stained positively with Alcian Blue and were associated with columnar cells. K corpuscles were oval, dark-brown multilamellar bodies and were associated with pyramidal cells. Under TEM, C corpuscles occurred within vacuoles of columnar cells and contained many electron-dense clumps and irregular membrane stacks and vesicles spread in an electron-lucent matrix. Sometimes a membrane appeared detached from the inner surface of the wall, suggesting the existence of a plasma membrane. In turn, K corpuscles were contained within vacuoles of pyramidal cells and were made of concentric lamellae, which were in turn made of an electron-dense fibrogranular material. No membranes were seen in them. Interspecifically, C corpuscles vary significantly in width and inner contents. K corpuscles were also variable in length and width. However, both C and K corpuscles in the three studied species hybridised with generalised cyanobacterial/chloroplast probes for 16S rRNA. Also, both corpuscle types (isolated from gland homogenates) were sensitive to lysozyme digestion, which indicates that bacterial peptidoglycans are an integral part of their covers. The reported data confirm and extend previous studies on P. canaliculata in which the endosymbiotic nature of C and K corpuscles were first proposed. We further propose that the endosymbiotic corpuscles are related to the Cyanobacteria/chloroplasts clade. Based on the known distribution of these corpuscles in the major clades of Ampullariidae, we hypothesise they may be universally distributed in this family, and that may constitute an interesting model for studying the co-evolution of endosymbionts and their gastropod hosts.

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Delayed-matching-to-position working memory in mice relies on NMDA-receptors in prefrontal pyramidal cells

Scientific Reports ◽

10.1038/s41598-021-88200-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Kasyoka Kilonzo ◽

Bastiaan van der Veen ◽

Jasper Teutsch ◽

Stefanie Schulz ◽

Sampath K. T. Kapanaiah ◽

...

Keyword(s):

Working Memory ◽

Pyramidal Cells ◽

Cell Types ◽

Delayed Matching ◽

Hedonic Valuation ◽

Distinct Cell ◽

Excitatory Neurons ◽

Processing Motivation ◽

The Brain ◽

Matching To Position

AbstractA hypofunction of N-methyl-D-aspartate glutamate receptors (NMDARs) has been implicated in the pathogenesis of schizophrenia by clinical and rodent studies. However, to what extent NMDAR-hypofunction in distinct cell-types across the brain causes different symptoms of this disease is largely unknown. One pharmaco-resistant core symptom of schizophrenia is impaired working memory (WM). NMDARs have been suggested to mediate sustained firing in excitatory neurons of the prefrontal cortex (PFC) that might underlie WM storage. However, if NMDAR-hypofunction in prefrontal excitatory neurons may indeed entail WM impairments is unknown. We here investigated this question in mice, in which NMDARs were genetically-ablated in PFC excitatory cells. This cell type-selective NMDAR-hypofunction caused a specific deficit in a delayed-matching-to-position (DMTP) 5-choice-based operant WM task. In contrast, T-maze rewarded alternation and several psychological functions including attention, spatial short-term habituation, novelty-processing, motivation, sociability, impulsivity, and hedonic valuation remained unimpaired at the level of GluN1-hypofunction caused by our manipulation. Our data suggest that a hypofunction of NMDARs in prefrontal excitatory neurons may indeed cause WM impairments, but are possibly not accounting for most other deficits in schizophrenia.

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VARIASI MORFOMETRI DAN KARAKTER MORFOLOGI KEONG MAS (Pomacea canaliculata) PADA SAWAH DI DESA ABIANSEMAL BADUNG-BALI

SIMBIOSIS Journal of Biological Sciences ◽

10.24843/jsimbiosis.2018.v06.i02.p06 ◽

2018 ◽

Vol 6 (2) ◽

pp. 60

Author(s):

I Gede Agus Suarmustika ◽

Ni Made Suartini ◽

Job Nico Subagio

Keyword(s):

Rice Field ◽

Shell Height ◽

Morphological Characteristics ◽

Rice Fields ◽

The Other ◽

Pomacea Canaliculata ◽

Snail Species ◽

Apple Snail ◽

Morphometric Characters ◽

Golden Apple Snail

The purpose of this study was to determine variations in morphology and morphological characteristics of golden apple snails (P. canaliculata) in rice fields in Abiansemal Village. Gold apple snails can be found living in fresh water, including lakes, rivers, small ditches and also in rice fields. Rice field habitats in Bali can still be found in Abiansemal village, Badung regency, but not much information has been disclosed about the snails in the rice field habitat, especially the golden apple snail species (P. canaliculata). Therefore, it is necessary to do research on the golden apple snails in Abiansemal Village. This research was carried out in rice fields located in Abiansemal Village, Abiansemal District, Badung Regency, Bali Province. The study was conducted from April to May 2017. Sampling of golden apple snail (P. canaliculata) was carried out in three plots of rice fields in three banjars in Abiansemal Village, namely in the Latu Sari, Banjar Aseman, and Juwet banjars. The rice field was chosen randomly and then in each selected field of rice the golden apple snail sample was taken using a 1x1m square. Samples on each plot of rice were taken three times. All samples of golden snail contained in the squared were taken and cleaned and then preserved with 70% alcohol. The golden apple snail sample obtained was calculated for its density and all morphological and morphometric characters were analyzed descriptively. In this study it was found that the morphology of golden apple snail patterned lines for morphometric characters, the shell height was higher in the banjar Juwet area, for the width of the shell mouth was greater in the banjar area Aseman and the height of the shell cover was higher in the banjar area of Latu Sari, while the morphology was plain patterned for morphometric characters, the height of the shell and the height of tendrils were higher in the banjar area of Latu Sari, and for the height and width of the cover the shell was higher and wider in the banjar area of Aseman, while for the other morphometric characters the results were found almost the same. Keywords: snail, rice field, morphology, morphometry

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Fine Structure of the Malpighian Tubules of the Mosquito, Culex pipiens

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010006605x ◽

1971 ◽

Vol 29 ◽

pp. 402-403

Author(s):

Brendan Clifford

Keyword(s):

Fine Structure ◽

Culex Pipiens ◽

Stellate Cell ◽

Malpighian Tubule ◽

Cell Types ◽

Instar Larva ◽

Malpighian Tubules ◽

Calliphora Erythrocephala ◽

Distinct Cell ◽

Basal Plasma

An ultrastructural investigation of the Malpighian tubules of the fourth instar larva of Culex pipiens was undertaken as part of a continuing study of the fine structure of transport epithelia.Each of the five Malpighian tubules was found to be morphologically identical and regionally undifferentiated. Two distinct cell types, the primary and stellate, were found intermingled along the length of each tubule. The ultrastructure of the stellate cell was previously described in the Malpighian tubule of the blowfly, Calliphora erythrocephala by Berridge and Oschman.The basal plasma membrane of the primary cell is extremely irregular, giving rise to a complex interconnecting network of basal channels. The compartments of cytoplasm entrapped within this system of basal infoldings contain mitochondria, free ribosomes, and small amounts of rough endoplasmic reticulum. The mitochondria are distinctive in that the cristae run parallel to the long axis of the organelle.

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Control of impulsivity by Gi-protein signalling in layer-5 pyramidal neurons of the anterior cingulate cortex

Communications Biology ◽

10.1038/s42003-021-02188-w ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Bastiaan van der Veen ◽

Sampath K. T. Kapanaiah ◽

Kasyoka Kilonzo ◽

Peter Steele-Perkins ◽

Martin M. Jendryka ◽

...

Keyword(s):

Gene Expression ◽

Anterior Cingulate Cortex ◽

Expression Analysis ◽

Gene Expression Analysis ◽

Pyramidal Neurons ◽

Treatment Options ◽

Pyramidal Cells ◽

Cingulate Cortex ◽

Cell Types ◽

Anterior Cingulate

AbstractPathological impulsivity is a debilitating symptom of multiple psychiatric diseases with few effective treatment options. To identify druggable receptors with anti-impulsive action we developed a systematic target discovery approach combining behavioural chemogenetics and gene expression analysis. Spatially restricted inhibition of three subdivisions of the prefrontal cortex of mice revealed that the anterior cingulate cortex (ACC) regulates premature responding, a form of motor impulsivity. Probing three G-protein cascades with designer receptors, we found that the activation of Gi-signalling in layer-5 pyramidal cells (L5-PCs) of the ACC strongly, reproducibly, and selectively decreased challenge-induced impulsivity. Differential gene expression analysis across murine ACC cell-types and 402 GPCRs revealed that - among Gi-coupled receptor-encoding genes - Grm2 is the most selectively expressed in L5-PCs while alternative targets were scarce. Validating our approach, we confirmed that mGluR2 activation reduced premature responding. These results suggest Gi-coupled receptors in ACC L5-PCs as therapeutic targets for impulse control disorders.

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Comparison of Invasive Apple Snail (Pomacea canaliculata) Behaviors in Different Water Temperature Gradients

Water ◽

10.3390/w13091149 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1149

Author(s):

Mi-Jung Bae ◽

Eui-Jin Kim ◽

Young-Seuk Park

Keyword(s):

Water Temperature ◽

Farming Systems ◽

Freshwater Snail ◽

Freshwater Ecosystems ◽

Pomacea Canaliculata ◽

Activity Levels ◽

Self Organizing Map ◽

Apple Snail ◽

Temperature Changes ◽

Organic Farming Systems

Pomacea canaliculata (known as invasive apple snail) is a freshwater snail native to South America that was introduced into many countries (including Asia and North America) as a food source or for organic farming systems. However, it has invaded freshwater ecosystems and become a serious agricultural pest in paddy fields. Water temperature is an important factor determining behavior and successful establishment in new areas. We examined the behavioral responses of P. canaliculata with water temperature changes from 25 °C to 30 °C, 20 °C, and 15 °C by quantifying changes in nine behaviors. At the acclimated temperature (25 °C), the mobility of P. canaliculata was low during the day, but high at night. Clinging behavior increased as the water temperature decreased from 25 °C to 20 °C or 15 °C. Conversely, ventilation and food consumption increased when the water temperature increased from 25 °C to 30 °C. A self-organizing map (an unsupervised artificial neural network) was used to classify the behavioral patterns into seven clusters at different water temperatures. These results suggest that the activity levels or certain behaviors of P. canaliculata vary with the water temperature conditions. Understanding the thermal biology of P. canaliculata may be crucial for managing this invasive snail.

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NF-κB in Cancer Immunity: Friend or Foe?

Cells ◽

10.3390/cells10020355 ◽

2021 ◽

Vol 10 (2) ◽

pp. 355

Author(s):

Guilhem Lalle ◽

Julie Twardowski ◽

Yenkel Grinberg-Bleyer

Keyword(s):

Immune Responses ◽

Therapeutic Potential ◽

Cell Types ◽

Transcriptional Activators ◽

New Class ◽

Complex Interactions ◽

Cancer Immunity ◽

Distinct Cell ◽

Cancer Initiation ◽

Cancer Outcome

The emergence of immunotherapies has definitely proven the tight relationship between malignant and immune cells, its impact on cancer outcome and its therapeutic potential. In this context, it is undoubtedly critical to decipher the transcriptional regulation of these complex interactions. Following early observations demonstrating the roles of NF-κB in cancer initiation and progression, a series of studies converge to establish NF-κB as a master regulator of immune responses to cancer. Importantly, NF-κB is a family of transcriptional activators and repressors that can act at different stages of cancer immunity. In this review, we provide an overview of the selective cell-intrinsic contributions of NF-κB to the distinct cell types that compose the tumor immune environment. We also propose a new view of NF-κB targeting drugs as a new class of immunotherapies for cancer.

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Glucocorticoid Receptor β (GRβ): Beyond Its Dominant-Negative Function

International Journal of Molecular Sciences ◽

10.3390/ijms22073649 ◽

2021 ◽

Vol 22 (7) ◽

pp. 3649

Author(s):

Patricia Ramos-Ramírez ◽

Omar Tliba

Keyword(s):

Current Knowledge ◽

Inflammatory Diseases ◽

Cell Communication ◽

Cell Types ◽

The Body ◽

Dominant Negative ◽

Negative Effects ◽

Independent Manner ◽

Distinct Cell ◽

Induced Apoptosis

Glucocorticoids (GCs) act via the GC receptor (GR), a receptor ubiquitously expressed in the body where it drives a broad spectrum of responses within distinct cell types and tissues, which vary in strength and specificity. The variability of GR-mediated cell responses is further extended by the existence of GR isoforms, such as GRα and GRβ, generated through alternative splicing mechanisms. While GRα is the classic receptor responsible for GC actions, GRβ has been implicated in the impairment of GRα-mediated activities. Interestingly, in contrast to the popular belief that GRβ actions are restricted to its dominant-negative effects on GRα-mediated responses, GRβ has been shown to have intrinsic activities and “directly” regulates a plethora of genes related to inflammatory process, cell communication, migration, and malignancy, each in a GRα-independent manner. Furthermore, GRβ has been associated with increased cell migration, growth, and reduced sensitivity to GC-induced apoptosis. We will summarize the current knowledge of GRβ-mediated responses, with a focus on the GRα-independent/intrinsic effects of GRβ and the associated non-canonical signaling pathways. Where appropriate, potential links to airway inflammatory diseases will be highlighted.

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Development, characterization, and applications of multi-material stereolithography bioprinting

Scientific Reports ◽

10.1038/s41598-021-82102-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Bagrat Grigoryan ◽

Daniel W. Sazer ◽

Amanda Avila ◽

Jacob L. Albritton ◽

Aparna Padhye ◽

...

Keyword(s):

Material Selection ◽

Cell Types ◽

Fluorescent Tracers ◽

Regional Feature ◽

Multicellular Aggregates ◽

Distinct Cell ◽

Adenocarcinoma Cells ◽

Mammalian Tissues ◽

Heterotypic Interactions ◽

Feature Alignment

AbstractAs a 3D bioprinting technique, hydrogel stereolithography has historically been limited in its ability to capture the spatial heterogeneity that permeates mammalian tissues and dictates structure–function relationships. This limitation stems directly from the difficulty of preventing unwanted material mixing when switching between different liquid bioinks. Accordingly, we present the development, characterization, and application of a multi-material stereolithography bioprinter that provides controlled material selection, yields precise regional feature alignment, and minimizes bioink mixing. Fluorescent tracers were first used to highlight the broad design freedoms afforded by this fabrication strategy, complemented by morphometric image analysis to validate architectural fidelity. To evaluate the bioactivity of printed gels, 344SQ lung adenocarcinoma cells were printed in a 3D core/shell architecture. These cells exhibited native phenotypic behavior as evidenced by apparent proliferation and formation of spherical multicellular aggregates. Cells were also printed as pre-formed multicellular aggregates, which appropriately developed invasive protrusions in response to hTGF-β1. Finally, we constructed a simplified model of intratumoral heterogeneity with two separate sub-populations of 344SQ cells, which together grew over 14 days to form a dense regional interface. Together, these studies highlight the potential of multi-material stereolithography to probe heterotypic interactions between distinct cell types in tissue-specific microenvironments.

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Annotation of chromatin states in 66 complete mouse epigenomes during development

Communications Biology ◽

10.1038/s42003-021-01756-4 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Arjan van der Velde ◽

Kaili Fan ◽

Junko Tsuji ◽

Jill E. Moore ◽

Michael J. Purcaro ◽

...

Keyword(s):

Target Genes ◽

Cell Types ◽

Developmental Trajectory ◽

Phase Iii ◽

Chromatin State ◽

Mammalian Development ◽

Chromatin States ◽

Transcription Start Sites ◽

Repressive Mark ◽

Distinct Cell

AbstractThe morphologically and functionally distinct cell types of a multicellular organism are maintained by their unique epigenomes and gene expression programs. Phase III of the ENCODE Project profiled 66 mouse epigenomes across twelve tissues at daily intervals from embryonic day 11.5 to birth. Applying the ChromHMM algorithm to these epigenomes, we annotated eighteen chromatin states with characteristics of promoters, enhancers, transcribed regions, repressed regions, and quiescent regions. Our integrative analyses delineate the tissue specificity and developmental trajectory of the loci in these chromatin states. Approximately 0.3% of each epigenome is assigned to a bivalent chromatin state, which harbors both active marks and the repressive mark H3K27me3. Highly evolutionarily conserved, these loci are enriched in silencers bound by polycomb repressive complex proteins, and the transcription start sites of their silenced target genes. This collection of chromatin state assignments provides a useful resource for studying mammalian development.

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