scholarly journals Cnidome and Morphological Features of Pelagia noctiluca (Cnidaria: Scyphozoa) Throughout the Different Life Cycle Stages

2021 ◽  
Vol 8 ◽  
Author(s):  
Ainara Ballesteros ◽  
Carina Östman ◽  
Andreu Santín ◽  
Macarena Marambio ◽  
Mridvika Narda ◽  
...  
Keyword(s):  
Life Cycle ◽  
Developmental Stages ◽  
Later Life ◽  
Life Stages ◽  
Accurate Identification ◽  
Early Stages ◽  
Pelagia Noctiluca ◽  
Life Cycle Stages ◽  
Advanced Stages ◽  
Stage 1

Pelagia noctiluca is considered the most important jellyfish in the Mediterranean Sea, due to its abundance and the severity of its stings. Despite its importance in marine ecosystems and the health problems caused by its massive arrival in coastal areas, little is known about its early life stages and its cnidome has never been described. This study of the morphological and anatomical features throughout the life cycle identifies four early stages: two ephyra and two metaephyra stages. Ephyra stage 1, newly developed from a planula, has no velar canals, gastric filaments or nematocyst batteries. Ephyra stage 2, has velar canals, a cruciform-shaped manubrium and gastric filaments. Metaephyra stage 3 has eight tentacle buds and nematocyst clusters for the first time. Lastly, in metaephyra stage 4, the eight primary tentacles grow nearly simultaneously, with no secondary tentacles. Complete nematocyst battery patterns gradually develop throughout the later life stages. Four nematocyst types are identified: a-isorhiza, A-isorhiza, O-isorhiza and eurytele. Of these, a-isorhiza and eurytele are the most important throughout the entire life cycle, while A-isorhiza and O-isorhiza have a more important role in advanced stages. All nematocysts show a positive correlation between increasing capsule volumes and increasing body diameter of the ephyrae, metaephyrae, young medusae and adult medusae. In the early stages, the volumes of euryteles in the gastric filaments are larger than those in the exumbrella, indicating that the capsule volume is critical in the absence of marginal tentacles, specialized for feeding. This study provides updated information, the most extensive description to date, including high-resolution photographs and schematic drawings of all the developmental stages in the life cycle of P. noctiluca. Additionally, the first cnidome characterization is provided for each stage to facilitate accurate identification of this species when collected in the water column, and to raise awareness of the potential for human envenomation.

scholarly journals Mitochondrial Processes during Early Development of Dictyostelium discoideum: From Bioenergetic to Proteomic Studies

Genes ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 638
Author(s):  
Monika Mazur ◽  
Daria Wojciechowska ◽  
Ewa Sitkiewicz ◽  
Agata Malinowska ◽  
Bianka Świderska ◽  
...  
Keyword(s):  
Life Cycle ◽  
Developmental Stages ◽  
Coupling Efficiency ◽  
Slime Mold ◽  
Intact Cells ◽  
Life Cycle Stages ◽  
Early Developmental Stages ◽  
Proteomic Study ◽  
And Function ◽  
Early Developmental

The slime mold Dictyostelium discoideum’s life cycle includes different unicellular and multicellular stages that provide a convenient model for research concerning intracellular and intercellular mechanisms influencing mitochondria’s structure and function. We aim to determine the differences between the mitochondria isolated from the slime mold regarding its early developmental stages induced by starvation, namely the unicellular (U), aggregation (A) and streams (S) stages, at the bioenergetic and proteome levels. We measured the oxygen consumption of intact cells using the Clarke electrode and observed a distinct decrease in mitochondrial coupling capacity for stage S cells and a decrease in mitochondrial coupling efficiency for stage A and S cells. We also found changes in spare respiratory capacity. We performed a wide comparative proteomic study. During the transition from the unicellular stage to the multicellular stage, important proteomic differences occurred in stages A and S relating to the proteins of the main mitochondrial functional groups, showing characteristic tendencies that could be associated with their ongoing adaptation to starvation following cell reprogramming during the switch to gluconeogenesis. We suggest that the main mitochondrial processes are downregulated during the early developmental stages, although this needs to be verified by extending analogous studies to the next slime mold life cycle stages.

Autonomy and integration in complex parasite life cycles

Parasitology ◽  
2016 ◽  
Vol 143 (14) ◽  
pp. 1824-1846 ◽  
Author(s):  
DANIEL P. BENESH
Keyword(s):  
Life Cycle ◽  
Holistic Approach ◽  
Life Cycles ◽  
Complex Life Cycle ◽  
Functional Specialization ◽  
Life Stages ◽  
Free Living ◽  
New Host ◽  
Complex Life Cycles ◽  
Life Cycle Stages

SUMMARYComplex life cycles are common in free-living and parasitic organisms alike. The adaptive decoupling hypothesis postulates that separate life cycle stages have a degree of developmental and genetic autonomy, allowing them to be independently optimized for dissimilar, competing tasks. That is, complex life cycles evolved to facilitate functional specialization. Here, I review the connections between the different stages in parasite life cycles. I first examine evolutionary connections between life stages, such as the genetic coupling of parasite performance in consecutive hosts, the interspecific correlations between traits expressed in different hosts, and the developmental and functional obstacles to stage loss. Then, I evaluate how environmental factors link life stages through carryover effects, where stressful larval conditions impact parasites even after transmission to a new host. There is evidence for both autonomy and integration across stages, so the relevant question becomes how integrated are parasite life cycles and through what mechanisms? By highlighting how genetics, development, selection and the environment can lead to interdependencies among successive life stages, I wish to promote a holistic approach to studying complex life cycle parasites and emphasize that what happens in one stage is potentially highly relevant for later stages.

scholarly journals Assessment of reference genes at six different developmental stages of Schistosoma mansoni for quantitative RT-PCR

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Gilbert O. Silveira ◽  
Murilo S. Amaral ◽  
Helena S. Coelho ◽  
Lucas F. Maciel ◽  
Adriana S. A. Pereira ◽  
...  
Keyword(s):  
Gene Expression ◽  
Life Cycle ◽  
Schistosoma Mansoni ◽  
Reference Genes ◽  
Large Scale ◽  
Developmental Stages ◽  
Adult Males ◽  
Histone H4 ◽  
Expression Levels ◽  
Life Cycle Stages

AbstractReverse-transcription quantitative real-time polymerase chain reaction (RT-qPCR) is the most used, fast, and reproducible method to confirm large-scale gene expression data. The use of stable reference genes for the normalization of RT-qPCR assays is recognized worldwide. No systematic study for selecting appropriate reference genes for usage in RT-qPCR experiments comparing gene expression levels at different Schistosoma mansoni life-cycle stages has been performed. Most studies rely on genes commonly used in other organisms, such as actin, tubulin, and GAPDH. Therefore, the present study focused on identifying reference genes suitable for RT-qPCR assays across six S. mansoni developmental stages. The expression levels of 25 novel candidates that we selected based on the analysis of public RNA-Seq datasets, along with eight commonly used reference genes, were systematically tested by RT-qPCR across six developmental stages of S. mansoni (eggs, miracidia, cercariae, schistosomula, adult males and adult females). The stability of genes was evaluated with geNorm, NormFinder and RefFinder algorithms. The least stable candidate reference genes tested were actin, tubulin and GAPDH. The two most stable reference genes suitable for RT-qPCR normalization were Smp_101310 (Histone H4 transcription factor) and Smp_196510 (Ubiquitin recognition factor in ER-associated degradation protein 1). Performance of these two genes as normalizers was successfully evaluated with females maintained unpaired or paired to males in culture for 8 days, or with worm pairs exposed for 16 days to double-stranded RNAs to silence a protein-coding gene. This study provides reliable reference genes for RT-qPCR analysis using samples from six different S. mansoni life-cycle stages.

The Black Parlatoria Scale, Parlatoria ziziphi (Lucas, 1853) (Hemiptera: Coccomorpha: Diaspididae): a guide to field identification

2020 ◽  
Vol 111 (1) ◽  
pp. 39-48
Author(s):  
Hanen Jendoubi ◽  
Ferran Garcia-Mari ◽  
Agatino Russo ◽  
Pompeo Suma
Keyword(s):  
Life Cycle ◽  
Developmental Stages ◽  
Invasive Pest ◽  
Sour Orange ◽  
Immature Stages ◽  
Male And Female ◽  
Distinctive Features ◽  
Life Cycle Stages ◽  
Field Identification ◽  
Correct Species Identification

AbstractPest control is easier and more effective when pests are correctly identified. The Black Parlatoria Scale, Parlatoria ziziphi (Lucas, 1853) (Hemiptera: Coccomorpha: Diaspididae) is an important invasive pest in citrus-growing countries. This diaspidid has historically been difficult to control, because its immature stages are difficult to identify due to confusion with similar Parlatoria species. No field descriptions of female or male developmental stages are available for P. ziziphi. We provide the first description of field characteristics of the developmental stages of P. ziziphi. Colonies were reared in the laboratory on sour orange plants and lemon fruits to illustrate the distinctive features of each instar. An illustrated field guide of all life-cycle stages of male and female P. ziziphi is provided for correct species identification and better pest management. This tool is designed to help recognize P. ziziphi in field-scouting programmes or quarantine inspections, without the need for taxonomic expertise in identifying the Parlatoria group.

Oxygen uptake in a barnacle: scaling to body size from nauplius to adult

1982 ◽  
Vol 60 (6) ◽  
pp. 1231-1235 ◽  
Author(s):  
D. D. Jorgensen ◽  
W. B. Vernberg
Keyword(s):  
Body Weight ◽  
Life Cycle ◽  
Oxygen Uptake ◽  
Naupliar Stage ◽  
Life Cycle Stages ◽  
Stage 1 ◽  
Balanus Eburneus ◽  
Adult Mass ◽  
The Relationship ◽  
Large Adult

We measured the oxygen uptake of the barnacle Balanus eburneus Gould during the following stages of its life cycle: (1) naupliar stages 1, 4 and 6; (2) cyprid; (3) postmetamorphosis adult (pinhead); and (4) large adult. Mass specific oxygen uptake [Formula: see text] increased by 60% during development from naupliar stage 1 to stage 6. An eightfold drop in [Formula: see text] occurred with the molt from stage 6 to cyprid. [Formula: see text] increased by fourfold after metamorphosis of the cyprid into the pinhead, the smallest adult. The slopes of the regression lines describing the relationship between nonmass specific O2 uptake and dry body weight (Wb) were (1) 1.27 for nauplii, (2) 0.87 for large adults, and (3) 0.75 for all life cycle stages studied except cyprids.

scholarly journals Comparative real-time PCR and enzyme analysis of selected gender-associated molecules inSchistosoma japonicum

Parasitology ◽  
2008 ◽  
Vol 135 (5) ◽  
pp. 575-583 ◽  
Author(s):  
L. MOERTEL ◽  
G. N. GOBERT ◽  
D. P. McMANUS
Keyword(s):  
Life Cycle ◽  
Real Time ◽  
Real Time Pcr ◽  
Developmental Stages ◽  
Enzyme Analysis ◽  
Parasitic Helminths ◽  
Life Cycle Stages ◽  
Gene Transcripts ◽  
Differential Transcription ◽  
Future Work

SUMMARYSchistosomes are complex parasitic helminths with discrete life-cycle stages, adapted for survival in their mammalian and snail hosts and the external aquatic environment. Recently, we described the fabrication and use of a microarray to investigate gender-specific transcription inSchistosoma japonicum. To address transcriptional differences, 8 gender-associated gene transcripts identified previously by the microarray analysis were selected for further study. First, differential transcription patterns were investigated in 4 developmental stages using real-time PCR. Subsequently, we undertook functional analysis of a subset of 4 transcripts encoding metabolic enzymes, so as to correlate gender-associated transcript levels with enzyme activity in protein extracts from adult worms. The 8 characterized molecules serve as a basis for further investigation of differential gene expression during the schistosome life-cycle and for studying the sexual dimorphism of adult worms. Continual refinement and annotation of the microarray used in the current study should support future work on these aspects.

scholarly journals From Metabolite to Metabolome: Metabolomics Applications in Plasmodium Research

2021 ◽  
Vol 11 ◽  
Author(s):  
Xinyu Yu ◽  
Gaoqian Feng ◽  
Qingfeng Zhang ◽  
Jun Cao
Keyword(s):  
Life Cycle ◽  
Life Stages ◽  
Disease Etiology ◽  
Malaria Research ◽  
Metabolic Mapping ◽  
The Past ◽  
Host Parasite Interactions ◽  
Life Cycle Stages ◽  
Parasite Biology ◽  
Host Parasite

Advances in research over the past few decades have greatly improved metabolomics-based approaches in studying parasite biology and disease etiology. This improves the investigation of varied metabolic requirements during life stages or when following transmission to their hosts, and fulfills the demand for improved diagnostics and precise therapeutics. Therefore, this review highlights the progress of metabolomics in malaria research, including metabolic mapping of Plasmodium vertebrate life cycle stages to investigate antimalarials mode of actions and underlying complex host-parasite interactions. Also, we discuss current limitations as well as make several practical suggestions for methodological improvements which could drive metabolomics progress for malaria from a comprehensive perspective.

scholarly journals Structure and Dynamics of the Gut Bacterial Community Across the Developmental Stages of the Coffee Berry Borer, Hypothenemus hampei

2021 ◽  
Vol 12 ◽  
Author(s):  
Fernan Santiago Mejía-Alvarado ◽  
Thaura Ghneim-Herrera ◽  
Carmenza E. Góngora ◽  
Pablo Benavides ◽  
Lucio Navarro-Escalante
Keyword(s):  
Life Cycle ◽  
Bacterial Community ◽  
Gut Microbiota ◽  
Developmental Stages ◽  
Life Stage ◽  
Insect Control ◽  
Life Stages ◽  
Hypothenemus Hampei ◽  
Coffee Berry ◽  
Structure And Dynamics

The coffee berry borer (CBB); Hypothenemus hampei (Coleoptera: Curculionidae), is widely recognized as the major insect pest of coffee crops. Like many other arthropods, CBB harbors numerous bacteria species that may have important physiological roles in host nutrition, detoxification, immunity and protection. To date, the structure and dynamics of the gut-associated bacterial community across the CBB life cycle is not yet well understood. A better understanding of the complex relationship between CBB and its bacterial companions may provide new opportunities for insect control. In the current investigation, we analyzed the diversity and abundance of gut microbiota across the CBB developmental stages under field conditions by using high-throughput Illumina sequencing of the 16S ribosomal RNA gene. Overall, 15 bacterial phyla, 38 classes, 61 orders, 101 families and 177 genera were identified across all life stages, including egg, larva 1, larva 2, pupa, and adults (female and male). Proteobacteria and Firmicutes phyla dominated the microbiota along the entire insect life cycle. Among the 177 genera, the 10 most abundant were members of Ochrobactrum (15.1%), Pantoea (6.6%), Erwinia (5.7%), Lactobacillus (4.3%), Acinetobacter (3.4%), Stenotrophomonas (3.1%), Akkermansia (3.0%), Agrobacterium (2.9%), Curtobacterium (2.7%), and Clostridium (2.7%). We found that the overall bacterial composition is diverse, variable within each life stage and appears to vary across development. About 20% of the identified OTUs were shared across all life stages, from which 28 OTUs were consistently found in all life stage replicates. Among these OTUs there are members of genera Pantoea, Erwinia, Agrobacterium, Ochrobactrum, Pseudomonas, Acinetobacter, Brachybacterium, Sphingomonas and Methylobacterium, which can be considered as the gut-associated core microbiota of H. hampei. Our findings bring additional data to enrich the understanding of gut microbiota in CBB and its possible use for development of insect control strategies.

scholarly journals Dynamics of venom composition across a complex life cycle

2017 ◽  
Author(s):  
Yaara Y. Columbus-Shenkar ◽  
Maria Y. Sachkova ◽  
Arie Fridrich ◽  
Vengamanaidu Modepalli ◽  
Kartik Sunagar ◽  
...  
Keyword(s):  
Life Cycle ◽  
Developmental Stages ◽  
Complex Life Cycle ◽  
Nematostella Vectensis ◽  
Life Stages ◽  
Early Life Stages ◽  
Sea Anemones ◽  
Sessile Polyp ◽  
Venom Composition ◽  
Production Dynamics

AbstractLittle is known about venom in young developmental stages of animals. The appearance of stinging cells in very early life stages of the sea anemone Nematostella vectensis suggests that toxins and venom are synthesized already in eggs, embryos and larvae of this species. Here we harness transcriptomic and biochemical tools as well as transgenesis to study venom production dynamics in Nematostella. We find that the venom composition and arsenal of toxin-producing cells change dramatically between developmental stages of this species. These findings might be explained by the vastly different ecology of the larva and adult polyp as sea anemones develop from a miniature non-feeding mobile planula to a much larger sessile polyp that predates on other animals. Further, the results suggest a much wider and dynamic venom landscape than initially appreciated in animals with a complex life cycle.

scholarly journals Rapid phenotypic evolution following shifts in life cycle complexity

2018 ◽  
Vol 285 (1871) ◽  
pp. 20172304 ◽  
Author(s):  
Ronald M. Bonett ◽  
John G. Phillips ◽  
Nicholus M. Ledbetter ◽  
Samuel D. Martin ◽  
Luke Lehman
Keyword(s):  
Life Cycle ◽  
Vertebral Column ◽  
Life Stages ◽  
Phenotypic Evolution ◽  
Trait Evolution ◽  
Life Cycle Stages ◽  
Biphasic Life Cycle ◽  
History Of ◽  
Life Cycle Evolution

Life cycle strategies have evolved extensively throughout the history of metazoans. The expression of disparate life stages within a single ontogeny can present conflicts to trait evolution, and therefore may have played a major role in shaping metazoan forms. However, few studies have examined the consequences of adding or subtracting life stages on patterns of trait evolution. By analysing trait evolution in a clade of closely related salamander lineages we show that shifts in the number of life cycle stages are associated with rapid phenotypic evolution. Specifically, salamanders with an aquatic-only (paedomorphic) life cycle have frequently added vertebrae to their trunk skeleton compared with closely related lineages with a complex aquatic-to-terrestrial (biphasic) life cycle. The rate of vertebral column evolution is also substantially lower in biphasic lineages, which may reflect the functional compromise of a complex cycle. This study demonstrates that the consequences of life cycle evolution can be detected at very fine scales of divergence. Rapid evolutionary responses can result from shifts in selective regimes following changes in life cycle complexity.

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