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

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

Biomolecules ◽

10.3390/biom9110702 ◽

2019 ◽

Vol 9 (11) ◽

pp. 702 ◽

Cited By ~ 6

Author(s):

Megan Aoki ◽

Anna Kisiala ◽

Shaojun Li ◽

Naomi Stock ◽

Craig Brunetti ◽

...

Keyword(s):

Life Cycle ◽

Dictyostelium Discoideum ◽

Spore Germination ◽

High Performance ◽

Developmental Stages ◽

Metabolomics Data ◽

Life Cycle Stages ◽

Cycle Growth ◽

And Function ◽

Exogenous Treatment

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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Coupling between ribotypic and phenotypic traits of protists across life-cycle stages and temperatures

10.1101/2020.12.28.424523 ◽

2020 ◽

Author(s):

Songbao Zou ◽

Rao Fu ◽

Qianqian Zhang ◽

Eleni Gentekaki ◽

Jun Gong

Keyword(s):

Growth Rate ◽

Life Cycle ◽

Single Cell ◽

Cell Volume ◽

Ribosomal Rna ◽

Life Cycle Stage ◽

Phenotypic Traits ◽

Distributional Pattern ◽

Life Cycle Stages ◽

Resting Cysts

ABSTRACTRelationships between ribotypic and phenotypic traits of protists across life-cycle stages remain largely unknown. Herein, we assessed the effect of life-cycle stage (lag, log, plateau, cyst) and temperature on quantity and polymorphisms of ribosomal (r)RNA gene (rDNA) and rRNA transcripts by using single cells of ciliate species. Colpoda inflata and C. steinii demonstrated allometric relationships between 18S rDNA copy number per cell (CNPC), cell volume (CV), and macronuclear volume across all life-cycle stages. Integrating previously reported data of Euplotes vannus and Strombidium sulcatum indicated taxon-dependent rDNA CNPC–CV functions. Ciliate and prokaryote data analysis revealed that the rRNA CNPC followed a unified power-law function, only if the rRNA-deficient resting cysts were not considered. Hence, a theoretical framework was proposed to estimate quantity of resting cysts of a protistan population. Using rDNA CNPC was a better predictor of growth rate at a given temperature than rRNA CNPC and CV, suggesting replication of redundant rDNA operons is a key factor that slows cell division. Single-cell high throughput sequencing revealed hundreds to thousands of rDNA and rRNA variants. The number of rDNA variants corresponded to the amount of cellular rDNA. Despite intra-individual divergence reaching up to 9%, operational taxonomic units (OTUs) clustered in a species-specific manner and independently of life-cycle stage or temperature. This indicates limited influence of said divergence on distributional pattern of OTU richness among samples.IMPORTANCEBased 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 ribosomal RNA gene (rDNA) and its transcripts have been widely used as molecular markers in ecological studies of protists. Nevertheless, the manner in which these molecules relate to cellular (organismal) and physiological traits remains poorly understood, which could lead to misinterpretations. The current research supports the idea that cellular ribosomal RNA transcript quantity reflects cell volume (biomass) of protists better than rDNA quantity, across multiple life-cycle stages except for resting cysts. We demonstrate that quantity of resting cysts and maximum growth rate of a population can be theoretically estimated using ribotypic trait-based formulas. Assessment of rDNA and rRNA sequence polymorphisms at single-cell level indicates that intra-individual divergence does not affect recognizing variational patterns of protistan diversity across time and space

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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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