Cytokinin Detection during the Dictyostelium discoideum Life Cycle: Profiles Are Dynamic and Affect Cell Growth and Spore Germination

Cytokinins (CKs) are a family of evolutionarily conserved growth regulating hormones. While CKs are well-characterized in plant systems, these N6-substituted adenine derivatives are found in a variety of organisms beyond plants, including bacteria, fungi, mammals, and the social amoeba, Dictyostelium discoideum. Within Dictyostelium, CKs have only been studied in the late developmental stages of the life cycle, where they promote spore encapsulation and dormancy. In this study, we used ultra high-performance liquid chromatography-positive electrospray ionization-high resolution tandem mass spectrometry (UHPLC-(ESI+)-HRMS/MS) to profile CKs during the Dictyostelium life cycle: growth, aggregation, mound, slug, fruiting body, and germination. Comprehensive profiling revealed that Dictyostelium produces 6 CK forms (cis-Zeatin (cZ), discadenine (DA), N6-isopentenyladenine (iP), N6-isopentenyladenine-9-riboside (iPR), N6-isopentenyladenine-9-riboside-5′ phosphate (iPRP), and 2-methylthio-N6-isopentenyladenine (2MeSiP)) in varying abundance across the sampled life cycle stages, thus laying the foundation for the CK biosynthesis pathway to be defined in this organism. Interestingly, iP-type CKs were the most dominant CK analytes detected during growth and aggregation. Exogenous treatment of AX3 cells with various CK types revealed that iP was the only CK to promote the proliferation of cells in culture. In support of previous studies, metabolomics data revealed that DA is one of the most significantly upregulated small molecules during Dictyostelium development, and our data indicates that total CK levels are highest during germination. While much remains to be explored in Dictyostelium, this research offers new insight into the nature of CK biosynthesis, secretion, and function during Dictyostelium growth, development, and spore germination.

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

Genes ◽

10.3390/genes12050638 ◽

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.

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

Frontiers in Marine Science ◽

10.3389/fmars.2021.714503 ◽

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.

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Guide to Native Bees of Australia

10.1071/9781486304073 ◽

2018 ◽

Cited By ~ 7

Author(s):

Terry Houston

Keyword(s):

Life Cycle ◽

Natural History ◽

Plant Material ◽

Morphological Characters ◽

Native Bees ◽

Nest Architecture ◽

Form And Function ◽

Genus Level ◽

Life Cycle Stages ◽

And Function

Bees are often thought of as yellow and black striped insects that live in hives and produce honey. However, Australia’s abundant native bees are incredibly diverse in their appearance and habits. Some are yellow and black but others have blue stripes, are iridescent green or wasp-like. Some are social but most are solitary. Some do build nests with wax but others use silk or plant material, burrow in soil or use holes in wood and even gumnuts! A Guide to Native Bees of Australia provides a detailed introduction to the estimated 2000 species of Australian bees. Illustrated with stunning photographs, it describes the form and function of bees, their life-cycle stages, nest architecture, sociality and relationships with plants. It also contains systematic accounts of the five families and 58 genera of Australian bees. Photomicrographs of morphological characters and identification keys allow identification of bees to genus level. Natural history enthusiasts, professional and amateur entomologists and beekeepers will find this an essential guide.

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

Scientific Reports ◽

10.1038/s41598-021-96055-7 ◽

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.

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

Bulletin of Entomological Research ◽

10.1017/s0007485320000279 ◽

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.

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

Parasitology ◽

10.1017/s0031182008004174 ◽

2008 ◽

Vol 135 (5) ◽

pp. 575-583 ◽

Cited By ~ 8

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.

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Coupling between Ribotypic and Phenotypic Traits of Protists across Life Cycle Stages and Temperatures

Microbiology Spectrum ◽

10.1128/spectrum.01738-21 ◽

2021 ◽

Author(s):

Songbao Zou ◽

Rao Fu ◽

Huiwen Deng ◽

Qianqian Zhang ◽

Eleni Gentekaki ◽

...

Keyword(s):

Molecular Markers ◽

Life Cycle ◽

Growth Potential ◽

Phenotypic Traits ◽

Rrna Gene ◽

Ecological Studies ◽

Life Cycle Stages ◽

And Function

Based on phenotypic traits, traditional surveys usually characterize organismal richness, abundance, biomass, and growth potential to describe diversity, organization, and function of protistan populations and communities. The rRNA gene (rDNA) and its transcripts have been widely used as molecular markers in ecological studies of protists.

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Gut Bacterial Diversity in Different Life Cycle Stages of Adelphocoris suturalis (Hemiptera: Miridae)

Frontiers in Microbiology ◽

10.3389/fmicb.2021.670383 ◽

2021 ◽

Vol 12 ◽

Author(s):

Hui Xue ◽

Xiangzhen Zhu ◽

Li Wang ◽

Kaixin Zhang ◽

Dongyang Li ◽

...

Keyword(s):

Life Cycle ◽

Relative Abundance ◽

High Throughput Sequencing ◽

Developmental Stages ◽

Control Strategies ◽

Symbiotic Bacteria ◽

Microbial Composition ◽

Agricultural Industry ◽

Life Cycle Stages ◽

Major Pest

Bacteria and insects have a mutually beneficial symbiotic relationship. Bacteria participate in several physiological processes such as reproduction, metabolism, and detoxification of the host. Adelphocoris suturalis is considered a pest by the agricultural industry and is now a major pest in cotton, posing a serious threat to agricultural production. As with many insects, various microbes live inside A. suturalis. However, the microbial composition and diversity of its life cycle have not been well-studied. To identify the species and community structure of symbiotic bacteria in A. suturalis, we used the HiSeq platform to perform high-throughput sequencing of the V3–V4 region in the 16S rRNA of symbiotic bacteria found in A. suturalis throughout its life stages. Our results demonstrated that younger nymphs (1st and 2nd instar nymphs) have higher species richness. Proteobacteria (87.06%) and Firmicutes (9.43%) were the dominant phyla of A. suturalis. At the genus level, Erwinia (28.98%), Staphylococcus (5.69%), and Acinetobacter (4.54%) were the dominant bacteria. We found that the relative abundance of Erwinia was very stable during the whole developmental stage. On the contrary, the relative abundance of Staphylococcus, Acinetobacter, Pseudomonas, and Corynebacterium showed significant dynamic changes at different developmental stages. Functional prediction of symbiotic bacteria mainly focuses on metabolic pathways. Our findings document symbiotic bacteria across the life cycle of A. suturalis, as well as differences in both the composition and richness in nymph and adult symbiotic bacteria. Our analysis of the bacteria in A. suturalis provides important information for the development of novel biological control strategies.

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Morphology and molecular analysis of life-cycle stages of Proctoeces maculatus (Looss, 1901) (Digenea: Fellodistomidae) in the Bizerte Lagoon, Tunisia

Journal of Helminthology ◽

10.1017/s0022149x15001030 ◽

2015 ◽

Vol 90 (6) ◽

pp. 726-736 ◽

Cited By ~ 5

Author(s):

R. Antar ◽

L. Gargouri

Keyword(s):

Life Cycle ◽

Intermediate Host ◽

Developmental Stages ◽

Sparus Aurata ◽

Morphological Identification ◽

Bizerte Lagoon ◽

Rdna Sequences ◽

Life Cycle Stages ◽

Mediterranean Mussel ◽

Second Intermediate Host

AbstractThe life cycle of Proctoeces maculatus (Looss, 1901) (Digenea, Fellodistomidae) was studied in Bizerte Lagoon (Tunisia). Three sequential hosts appear to be involved: the Mediterranean mussel Mytilus galloprovincialis Lamarck, 1819 (Mytilidae) as the first intermediate host; the polychaete Sabella pavonina Savigny, 1822 (Sabellidae), as the second intermediate host; and fishes (Lithognathus mormyrus (Linnaeus, 1758) (Sparidae), Trachinotus ovatus (Linnaeus, 1758) (Carangidae) and Sparus aurata Linnaeus, 1758 (Sparidae) as the definitive hosts. It should be noted that S. pavonina was recorded as second intermediate host for P. maculatus for the first time. Molecular confirmation of the morphological identification of the life-cycle stages of this digenean was obtained using partial 28S rDNA sequences. Comparative sequences revealed that the sporocysts and the metacercariae are conspecific but they diverged by 0.3% from the adults. The present results raised the possibility of the existence of cryptic species within the different developmental stages. However, all the present isolates differed from material from Archosargus probatocephalus in the Gulf of Mexico identified as P. maculatus.

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Positional dynamics and glycosomal recruitment of developmental regulators during trypanosome differentiation

10.1101/603258 ◽

2019 ◽

Author(s):

Balázs Szöőr ◽

Dorina V. Simon ◽

Federico Rojas ◽

Julie Young ◽

Derrick R. Robinson ◽

...

Keyword(s):

Life Cycle ◽

Tyrosine Phosphatase ◽

Sub Saharan Africa ◽

Metabolic Adaptation ◽

Tsetse Flies ◽

African Trypanosomes ◽

Signalling Molecules ◽

Life Cycle Stages ◽

Sub Saharan ◽

And Function

AbstractGlycosomes are peroxisome-related organelles that compartmentalise the glycolytic enzymes in kinetoplastid parasites. These organelles are developmentally regulated in their number and composition, allowing metabolic adaptation to the parasite’s needs in the blood of mammalian hosts or within their arthropod vector. A protein phosphatase cascade regulates differentiation between parasite developmental forms, comprising a tyrosine phosphatase, TbPTP1, that dephosphorylates and inhibits a serine threonine phosphatase TbPIP39 that promotes differentiation. When TbPTP1 is inactivated, TbPIP39 is activated and during differentiation becomes located in glycosomes. Here we have tracked TbPIP39 recruitment to glycosomes during differentiation from bloodstream stumpy forms to procyclic forms. Detailed microscopy and live cell imaging during the synchronous transition between life cycle stages revealed that in stumpy forms, TbPIP39 is located at a periflagellar pocket site closely associated with TbVAP, that defines the flagellar pocket endoplasmic reticulum. TbPTP1 is also located at the same site in stumpy forms, as is REG9.1, a regulator of stumpy-enriched mRNAs. This site provides a molecular node for the interaction between TbPTP1 and TbPIP39. Within 30 minutes of the initiation of differentiation TbPIP39 relocates to glycosomes whereas TbPTP1 disperses to the cytosol. Overall, the study identifies a ‘stumpy regulatory nexus’ (STuRN) that co-ordinates the molecular components of life cycle signalling and glycosomal development during transmission ofTrypanosoma brucei.ImportanceAfrican trypanosomes are parasites of sub-Saharan Africa responsible for both human and animal disease. The parasites are transmitted by tsetse flies and completion of their life cycle involves progression through several development steps. The initiation of differentiation between blood and tsetse forms is signalled by a phosphatase cascade, ultimately trafficked into peroxisome-related organelles called glycosomes that are unique to this group of organisms. Glycosomes undergo substantial remodelling of their composition and function during the differentiation step but how this is regulated is not understood. Here we identify a cytological site where the signalling molecules controlling differentiation converge before the dispersal of one of them into glycosomes. This coincides with a specialised ER site that may contribute to glycosome developmental biogenesis or regeneration. In combination, the study provides the first insight into the spatial co-ordination of signalling pathway components in trypanosomes as they undergo cell-type differentiation.

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