Noncanonical usage of stop codons in ciliates expands proteins with structurally flexible Q-rich motifs DOI Creative Commons
Chi-Ning Chuang, Hou-Cheng Liu, Tai-Ting Woo

и другие.

eLife, Год журнала: 2024, Номер 12

Опубликована: Фев. 23, 2024

Serine(S)/threonine(T)-glutamine(Q) cluster domains (SCDs), polyglutamine (polyQ) tracts and polyglutamine/asparagine (polyQ/N) are Q-rich motifs found in many proteins. SCDs often intrinsically disordered regions that mediate protein phosphorylation protein-protein interactions. PolyQ polyQ/N structurally flexible sequences trigger aggregation. We report due to their high percentages of STQ or STQN amino acid content, four three prion-causing Q/N-rich yeast proteins possess autonomous expression-enhancing activities. Since these can endow with structural functional plasticity, we suggest they represent useful toolkits for evolutionary novelty. Comparative Gene Ontology (GO) analyses the near-complete proteomes 26 representative model eukaryotes reveal prevail involved specialized biological processes, including Saccharomyces cerevisiae RNA-mediated transposition pseudohyphal growth, Candida albicans filamentous ciliate peptidyl-glutamic modification microtubule-based movement, Tetrahymena thermophila xylan catabolism meiosis, Dictyostelium discoideum development sexual cycles, Plasmodium falciparum infection, nervous systems Drosophila melanogaster, Mus musculus Homo sapiens . also show Q-rich-motif expanded massively 10 ciliates reassigned TAA Q TAG codons. Notably, usage frequency CAG is much lower codons than organisms unstable runs (e.g. D. melanogaster H. ), indicating use noncanonical stop may have coevolved codon biases avoid triplet repeat disorders mediated by CAG/GTC replication slippage.

Язык: Английский

Meiosis: Dances Between Homologs DOI Creative Commons

Denise Zickler,

Nancy Kleckner

Annual Review of Genetics, Год журнала: 2023, Номер 57(1), С. 1 - 63

Опубликована: Окт. 3, 2023

The raison d'être of meiosis is shuffling genetic information via Mendelian segregation and, within individual chromosomes, by DNA crossing-over. These outcomes are enabled a complex cellular program in which interactions between homologous chromosomes play central role. We first provide background regarding the basic principles this program. then summarize current understanding events recombination and three processes that involve whole chromosomes: homolog pairing, crossover interference, chiasma maturation. All these implemented direct physical interaction complexes with underlying chromosome structures. Finally, we present convergent lines evidence meiotic may have evolved coupling to late-stage mitotic morphogenesis.

Язык: Английский

Процитировано

82
RebL1 is required for macronuclear structure stability and gametogenesis in Tetrahymena thermophila DOI Creative Commons

Huijuan Hao,

Yinjie Lian,

Chenhui Ren

и другие.

Marine Life Science & Technology, Год журнала: 2024, Номер 6(2), С. 183 - 197

Опубликована: Март 26, 2024

Histone modification and nucleosome assembly play important roles in chromatin-related processes. chaperones form different complexes coordinate histone transportation assembly. Various chaperone have been identified organisms. The ciliate protozoa (ciliates) various chromatin structures nuclear morphology. However, components functions of subunits remain unclear ciliates.

Язык: Английский

Процитировано

7
From conservation to adaptation: understanding the synaptonemal complex’s evolutionary dynamics DOI Creative Commons
S. M. Williams, R. Scott Hawley

Current Opinion in Genetics & Development, Год журнала: 2025, Номер 93, С. 102349 - 102349

Опубликована: Апрель 17, 2025

The synaptonemal complex (SC) is structurally conserved across eukaryotes and essential for a proper progression of meiosis. Despite this conservation, SC protein sequences diverge drastically. In review, we explore findings on evolution, highlighting key differences commonalities among lineages like the Caenorhabditis Drosophila genera. We further known cases where its proteins adopt novel functional roles discuss why knowledge these could be important study canonical biology. existing studies demonstrate that work evolutionary biology in more diverse meiotic research organisms should play major role aiding our understanding structure functions.

Язык: Английский

Процитировано

1
Cultivation of fish ciliate parasites: Progress and prospects DOI
Ming Li, Giana Bastos Gomes, Weishan Zhao

и другие.

Reviews in Aquaculture, Год журнала: 2022, Номер 15(1), С. 142 - 162

Опубликована: Июль 13, 2022

Abstract Ciliates are considered the most harmful parasites of fish, causing mass mortalities and thus substantial economic losses to aquaculture ornamental fish industries. To better elucidate their pathogenic mechanisms facilitate development effective prevention control strategies, it is essential apply novel technologies ensure continuous sufficient supply parasite specimens. This review discusses latest research progress in artificial culture six important parasitic ciliates affecting both freshwater marine globally: Ichthyophthirius multifiliis , Cryptocaryon irritans Chilodonella ( C. hexasticha piscicola uncinata ), Balantidium ctenopharyngodoni Scuticociliatida gen. spp., Tetrahymena spp. Methods for vitro vivo as well cryopreservation/preservation (depending on specific species) these organisms described herein. Challenges future applications also discussed.

Язык: Английский

Процитировано

29
How and Why Chromosomes Interact with the Cytoskeleton during Meiosis DOI Open Access
Hyung Jun Kim, Chenshu Liu, Abby F. Dernburg

и другие.

Genes, Год журнала: 2022, Номер 13(5), С. 901 - 901

Опубликована: Май 18, 2022

During the early meiotic prophase, connections are established between chromosomes and cytoplasmic motors via a nuclear envelope bridge, known as LINC (linker of nucleoskeleton cytoskeleton) complex. These widely conserved links can promote both chromosome motions. Studies in diverse organisms have illuminated molecular architecture these connections, but important questions remain regarding how they contribute to processes. Here, we summarize current knowledge field, outline challenges studying dynamics, highlight distinctive features that been characterized major model systems.

Язык: Английский

Процитировано

26
Life cycle strategies in free‐living unicellular eukaryotes: Diversity, evolution, and current molecular tools to unravel the private life of microorganisms DOI Creative Commons
Iris Rizos, Miguel J. Frada, Lucie Bittner

и другие.

Journal of Eukaryotic Microbiology, Год журнала: 2024, Номер 71(6)

Опубликована: Июль 31, 2024

An astonishing range of morphologies and life strategies has arisen across the vast diversity protists, allowing them to thrive in most environments. In model like Tetrahymena, Dictyostelium, or Trypanosoma, cycles involving multiple stages with different have been well characterized. contrast, knowledge free-living which primarily consist uncultivated environmental lineages, remains largely fragmentary. Various lineage-specific cellular innovations observed field for but such generally lack functional characterization unknown physiological ecological roles. actual state knowledge, evidence sexual processes is confirmed 20% protist lineages. Nevertheless, at onset eukaryotic diversification, common molecular trends emerged promote genetic recombination, establishing sex as an inherent feature protists. Here, we review from viewpoint cycle transitions genetics major We focus on scarcely summarizing its existence describing key genes governing progression, as, current methods studying both cultivable groups.

Язык: Английский

Процитировано

6
A practical reference for studying meiosis in the model ciliate Tetrahymena thermophila DOI
Miao Tian, Xia Cai, Yujie Liu

и другие.

Marine Life Science & Technology, Год журнала: 2022, Номер 4(4), С. 595 - 608

Опубликована: Ноя. 22, 2022

Язык: Английский

Процитировано

21
A SUMO E3 ligase promotes long non-coding RNA transcription to regulate small RNA-directed DNA elimination DOI Creative Commons
Salman Shehzada, Tomoko Noto, Julie Saksouk

и другие.

eLife, Год журнала: 2024, Номер 13

Опубликована: Янв. 10, 2024

Small RNAs target their complementary chromatin regions for gene silencing through nascent long non-coding (lncRNAs). In the ciliated protozoan Tetrahymena, interaction between Piwi-associated small (scnRNAs) and lncRNA transcripts from somatic genome has been proposed to induce target-directed RNA degradation (TDSD), scnRNAs not targeted TDSD later germline-limited sequences programmed DNA elimination. this study, we show that SUMO E3 ligase Ema2 is required accumulation of lncRNAs thus completing elimination make viable sexual progeny. interacts with E2 conjugating enzyme Ubc9 enhances SUMOylation transcription regulator Spt6. We further promotes association Spt6 polymerase II chromatin. These results suggest Ema2-directed actively transcription, which a prerequisite communication RNAs.

Язык: Английский

Процитировано

4
Meiosis in Plasmodium: how does it work? DOI Creative Commons
David S. Guttery, Mohammad Zeeshan, Anthony A. Holder

и другие.

Trends in Parasitology, Год журнала: 2023, Номер 39(10), С. 812 - 821

Опубликована: Авг. 2, 2023

Meiosis is sexual cell division, a process in eukaryotes whereby haploid gametes are produced. Compared to canonical model eukaryotes, meiosis apicomplexan parasites appears diverge from the with respect molecular mechanisms involved; biology of Plasmodium meiosis, and its regulation by means post-translational modification, largely unexplored. Here, we discuss impact technological advances biology, evolutionary bioinformatics, genome-wide functional studies on our understanding Apicomplexa. These parasites, including falciparum, Toxoplasma gondii, Eimeria spp., have significant socioeconomic human animal health. Understanding this key stage during parasite's life cycle may well reveal attractive targets for therapeutic intervention.

Язык: Английский

Процитировано

9
A specialized TFIIB is required for transcription of transposon-targeting noncoding RNAs DOI Creative Commons
Xia Cai,

Z H Zhai,

Tomoko Noto

и другие.

Nucleic Acids Research, Год журнала: 2025, Номер 53(9)

Опубликована: Май 10, 2025

Abstract Transposable elements (TEs) pose threats to genome stability. Therefore, small RNA-mediated heterochromatinization suppresses the transcription and hence mobility of TEs. Paradoxically, noncoding RNA (ncRNA) from TEs is needed for production TE-targeting RNAs and/or recruiting silencing machinery Hence, specialized polymerase II (Pol II) regulators are required such unconventional in different organisms, including developmental stage-specific Mediator complex (Med)-associated proteins ncRNA TE-related sequences Tetrahymena. Yet it remains unclear how Pol transcriptional assembled at transcription. Here, we report that regulated by Emit3, a TFIIB-like protein TE Emit3 interacts with TFIIH localizes TE-dense regions, especially sites enriched G-rich sequence motif. Deletion globally abolishes II-chromatin association meiotic nucleus, disrupts chromatin binding Med, impairs TE-biased localization TFIIH. Conversely, Emit3’s preferential TE-rich loci relies part on Med-associated proteins. These findings suggest TFIIH, work together initiate possibly sequence-dependent manner.

Язык: Английский

Процитировано

0