Ovary organization and ultrastructure in six species of Amynthas and Metaphire earthworms (Annelida, Crassiclitellata, Megascolecidae) DOI Creative Commons
Piotr Świątek,

Rojen Singh Thounaojam,

Th. Binoy Singh

et al.

Zoology, Journal Year: 2023, Volume and Issue: 160, P. 126109 - 126109

Published: Aug. 10, 2023

Ovaries in earthworms belonging to the family Megascolecidae are paired structures attached septum anterior part of XIII segment. They fan rosette shaped with numerous rows growing oocytes, known as egg strings, radiating from ovary center towards segmental cavity. The histological and ultrastructural organization megascolecids course oogenesis remain unknown. paper presents results light electron microscopy analyses ovaries six megascolecid species, three genus Amynthas Metaphire. Both parthenogenetic sexually reproducing species were included study. ultrastructure all studied broadly similar. Considering ovaries, they could be divided into two zones. Zone I (proximal, close connection septum) is tightly packed germline somatic cells. Germ cells interconnected via intercellular bridges thin strands central cytoplasm (known cytophore) form syncytial cysts. Cysts unite oogonia, early meiotic (till diplotene), clustering develop synchronously. During diplotene, lose developmental synchrony; most probably, one cell per cyst grows faster than others, detaches cysts, becomes an oocyte. remaining grow slightly still reticular cytophore; these considered nurse II has a strings where oocytes isolated another by short cords. We present details propose term "Amynthas" type for this organization. suppose that such characteristic other related families.

Language: Английский

High-throughput single-cell analysis reveals progressive mitochondrial DNA mosaicism throughout life DOI Creative Commons
Angelos Glynos, Lyuba V. Bozhilova, Michele Frison

et al.

Science Advances, Journal Year: 2023, Volume and Issue: 9(43)

Published: Oct. 25, 2023

Heteroplasmic mitochondrial DNA (mtDNA) mutations are a major cause of inherited disease and contribute to common late-onset human disorders. The late onset clinical progression mtDNA-associated is thought be due changing heteroplasmy levels, but it not known how when this occurs. Performing high-throughput single-cell genotyping in two mouse models mtDNA disease, we saw unanticipated cell-to-cell differences levels that emerged prenatally progressively increased throughout life. Proliferating spleen cells nondividing brain had similar variance, implicating or organelle turnover as the force determining cell levels. different segregated at rates with no evidence selection, consistent random genetic drift vivo, leading accumulation very high mutation burden rates. This provides an explanation for severity seen diseases caused by mutations.

Language: Английский

Citations

9
Genome dilution by cell growth drives starvation-like proteome remodeling in mammalian and yeast cells DOI Open Access
Michael C. Lanz, Shuyuan Zhang, Matthew P. Swaffer

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Oct. 19, 2023

SUMMARY Cell size is tightly controlled in healthy tissues and single-celled organisms, but it remains unclear how influences cell physiology. Increasing was recently shown to remodel the proteomes of cultured human cells, demonstrating that large small cells same type can be biochemically different. Here, we corroborate these results mouse hepatocytes extend our analysis using yeast. We find size-dependent proteome changes are highly conserved mostly independent metabolic state. As eukaryotic grow larger, dilution genome elicits a starvation-like phenotype, suggesting growth limited by manner analogous limiting nutrient. also this phenomenon explains many proteomic ascribed yeast aging. Overall, data suggest concentration universal determinant content growing cells.

Language: Английский

Citations

7
Epigenetic programming in the ovarian reserve DOI
Mengwen Hu, Richard M. Schultz, Satoshi H. Namekawa

et al.

BioEssays, Journal Year: 2023, Volume and Issue: 45(10)

Published: July 7, 2023

Abstract The ovarian reserve defines female reproductive lifespan, which in humans spans decades. consists of oocytes residing primordial follicles arrested meiotic prophase I and is maintained independent DNA replication cell proliferation, thereby lacking stem cell‐based maintenance. Largely unknown how cellular states the are established for Our recent study revealed that a distinct chromatin state during formation mice, uncovering novel window epigenetic programming germline development. We showed an regulator, Polycomb Repressive Complex 1 (PRC1), establishes repressive perinatal mouse essential I‐arrested to form reserve. Here we discuss biological roles mechanisms underlying formation, highlighting current knowledge gaps emerging research areas biology.

Language: Английский

Citations

6
The Ancient Origin and Function of Germline Cysts DOI
Allan C. Spradling

Results and problems in cell differentiation, Journal Year: 2023, Volume and Issue: unknown, P. 3 - 21

Published: Nov. 23, 2023

Language: Английский

Citations

6
Epigenetic aging of mammalian gametes DOI Creative Commons
Michael Klutstein, Nitzan Gonen

Molecular Reproduction and Development, Journal Year: 2023, Volume and Issue: 90(12), P. 785 - 803

Published: Nov. 24, 2023

Abstract The process of aging refers to physiological changes that occur an organism as time progresses and involves DNA, proteins, metabolism, cells, organs. Like the rest cells in body, gametes age, it is well established there a decline reproductive capabilities females males with aging. One major pathways known be involved epigenetic changes. epigenome multitude chemical modifications performed on DNA chromatin affect ability transcribed. In this review, we explore effects female male focus throughout Quality oocytes occurs at relatively early age. Epigenetic constitute important part oocyte methylation reduced along expression methyltransferases (DNMTs). Histone deacetylases (HDAC) also reduced, loss heterochromatin marks As consequence loss, retrotransposon elevated, aged suffer from damage. sperm, affects sperm number, motility fecundity, may process. 5 methyl‐cytosine (5mC) elevated men, but Long interspersed nuclear elements (LINE) reduced. Di trimethylation histone 3 lysine 9 (H3K9me2/3) men 27 (H3K27me3) elevated. protamine makeup changed, misbalanced ratio between proteins P1 P2. study recently gaining interest. current status field suggests many aspects gamete are still open for investigation. clinical applications these investigations have far‐reaching consequences fertility sociological human behavior.

Language: Английский

Citations

6
Single-nucleus atlas of the Artemia female reproductive system suggests germline repression of the Z chromosome DOI Creative Commons
Marwan Elkrewi, Beatriz Viçoso

PLoS Genetics, Journal Year: 2024, Volume and Issue: 20(8), P. e1011376 - e1011376

Published: Aug. 30, 2024

Our understanding of the molecular pathways that regulate oogenesis and define cellular identity in Arthropod female reproductive system extent their conservation is currently very limited. This due to focus on model systems, including Drosophila Daphnia, which do not reflect observed diversity morphologies, modes, sex chromosome systems. We use single-nucleus RNA ATAC sequencing produce a comprehensive single nucleus atlas adult Artemia franciscana system. map our data Fly Cell Atlas dataset melanogaster ovary, shedding light conserved regulatory programs between two distantly related species. identify major cell types known be present germ cells, follicle ovarian muscle cells. Additionally, we cells explore gene regulation expression Z during meiosis, highlighting its unique dynamics allowing us presence meiotic silencing this group.

Language: Английский

Citations

2
A High-Throughput Method for Quantifying Drosophila Fecundity DOI Creative Commons

A. Soler Gómez,

Sergio González, Ashwini Oke

et al.

Toxics, Journal Year: 2024, Volume and Issue: 12(9), P. 658 - 658

Published: Sept. 9, 2024

The fruit fly, Drosophila melanogaster, is an experimentally tractable model system that has recently emerged as a powerful “new approach methodology” (NAM) for chemical safety testing. As oogenesis well conserved at the molecular and cellular level, measurements of fecundity can be useful identifying chemicals affect reproductive health across species. However, standard assays have been difficult to perform in high-throughput manner because experimental factors such physiological state flies environmental cues must carefully controlled achieve consistent results. In addition, exposing large number different conditions (such additives diet) manually counting eggs laid determine impact on time-consuming. We overcome these challenges by combining new multiwell fly culture strategy with novel 3D-printed transfer device rapidly accurately from one plate another, RoboCam, low-cost, custom-built robotic camera capture images wells automatically, image segmentation pipeline automatically identify quantify eggs. show this method compatible robust egg laying throughout assay period demonstrate automated quantifying very accurate (r2 = 0.98 correlation between counts ground truth). we used efficiently detect effects induced dietary exposure chemicals. Taken together, substantially increases efficiency reproducibility egg-laying require multiple media conditions.

Language: Английский

Citations

2
The bHLH-PAS transcriptional complex Sim:Tgo plays active roles in late oogenesis to promote follicle maturation and ovulation DOI Open Access

Rebecca Oramas,

Elizabeth M Knapp, Baosheng Zeng

et al.

Development, Journal Year: 2023, Volume and Issue: 150(12)

Published: May 23, 2023

Across species, ovulation is a process induced by myriad of signaling cascades that ultimately leads to the release encapsulated oocytes from follicles. Follicles first need mature and gain ovulatory competency before ovulation; however, pathways regulating follicle maturation are incompletely understood in Drosophila other species. Our previous work has shown bHLH-PAS transcription factor Single-minded (Sim) plays important roles downstream nuclear receptor Ftz-f1 Drosophila. Here, we demonstrate Tango (Tgo), another protein, acts as co-factor Sim promote cell differentiation stages 10 12. In addition, discover re-upregulation stage-14 cells also essential upregulating octopamine mushroom body (OAMB), matrix metalloproteinase 2 (Mmp2) NADPH oxidase (NOX), either independently or conjunction with zinc-finger protein Hindsight (Hnt). All these factors crucial for successful ovulation. Together, our indicates transcriptional complex Sim:Tgo multiple late-stage

Language: Английский

Citations

4
Delayed abscission in animal cells – from development to defects DOI Open Access

Snježana Kodba,

Agathe Chaigne

Journal of Cell Science, Journal Year: 2023, Volume and Issue: 136(13)

Published: June 30, 2023

ABSTRACT Cell division involves separating the genetic material and cytoplasm of a mother cell into two daughter cells. The last step division, abscission, consists cutting cytoplasmic bridge, microtubule-rich membranous tube connecting cells, which contains midbody, dense proteinaceous structure. Canonically, abscission occurs 1–3 h after anaphase. However, in certain cases, can be severely delayed or incomplete. Abscission delays caused by mitotic defects that activate ‘NoCut’ checkpoint tumor as well when cells exert abnormally strong pulling forces on bridge. Delayed also occur during normal organism development. Here, we compare mechanisms triggering incomplete healthy disease scenarios. We propose NoCut is not bona fide cycle checkpoint, but general mechanism control dynamics multiple contexts.

Language: Английский

Citations

4
A tug-of-war between germ cell motility and intercellular bridges controls germline cyst formation in mice DOI
Ezra Levy,

Isabella Leite,

Bradley Joyce

et al.

Current Biology, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 1, 2024

Language: Английский

Citations

1