The Centriolar Damage Accumulation Theory of Aging (CDATA) proposes that the mother centriole in adult stem cells functions as an irreversible molecular damage accumulator, whose progressive deterioration drives the decline of tissue homeostasis and organismal aging. While theoretically compelling, CDATA has faced valid criticisms regarding the correlation-vs.-causation problem, the non-universality of asymmetric centriole inheritance, the specificity of the centriole over other long-lived organelles, and an internal contradiction regarding cancer biology. Here I present the Cell DT platform — a computational digital twin of CDATA — that provides the first mechanistic, quantitative, and internally consistent model of centriolar aging. Implemented in Rust using an Entity-Component-System (ECS) architecture, the platform models five molecular damage types (protein carbonylation, tubulin hyperacetylation, protein aggregation, phosphorylation dysregulation, and distal appendage loss), two downstream failure tracks (Track A: ciliary signaling failure; Track B: asymmetric division failure), and a positive ROS feedback loop. Simulations of 36,500 daily time steps reproduce a human lifespan of approximately 78–83 years under normal conditions, approximately 15–20 years under progeria-like parameters (5× damage rates), and approximately 130 years under longevity-associated parameters (0.6× rates). I systematically address each major critique of CDATA, showing that: (1) the digital twin provides mechanistic causal evidence beyond correlation; (2) stochastic asymmetric division suffices to drive CDATA dynamics even in tissues with predominantly symmetric divisions; (3) the centriole is uniquely positioned as a non-renewable, template-replicated hub integrating both ciliary and spindle functions; and (4) the cancer-aging paradox is resolved by two distinct failure modes of the same underlying mechanism. I conclude that CDATA is a falsifiable, computationally validated hypothesis that warrants experimental testing with the priority experiments outlined herein.

The centrosome, classically defined as the primary microtubule-organizing center of the animal cell, is here reconceptualized as a critical organelle for non-genomic cellular memory. We propose the Centrosomal Ledger hypothesis, which posits that the mother centriole encodes a high-dimensional molecular state vector. This distributed memory integrates proteomic composition, post-translational modification (PTM) landscapes, and macromolecular stoichiometries accumulated over a cell’s history. Rather than being a passive structural hub, the centrosome actively utilizes this integrated record to guide future cell fate decisions, such as the choice between symmetric and asymmetric division. Crucically, this hypothesis is untestable by traditional bulk-cell molecular biology, as it requires the discrimination of centriole-age-specific molecular signatures. Its rigorous falsification necessitates centrosome-resolved, multi-omic approaches. Furthermore, we argue that dysregulation of this ledger—through corruption or erosion—constitutes a fundamental mechanistic axis underlying oncogenic transformation, where fate instruction is scrambled, and age-associated stem cell decline, where instructive fidelity is lost. This reframing of the centrosome from a cytoskeletal architect to an information-processing device opens novel translational avenues for diagnosing and treating cancer and degenerative diseases by targeting organelle memory.

The centrosome is fundamentally recognized for its role in cell division and ciliogenesis. However, emerging evidence suggests a non-canonical function: the centriole, particularly the mother centriole, acts as a regulatory hub for cellular differentiation. This article synthesizes data from 65 studies (2010–2024) to test the hypothesis that centrioles are associated with unique sets of regulatory molecules which, upon specific cues, can act as local inducers of cell fate. We systematically identify and classify such Centriole-Associated Fate Determinants (CAFDs), including transcription factors (STAT3, YAP/TAZ, Gli), RNA regulators (Prospero mRNA), kinases (PLK4), and ubiquitin ligase components. We delineate four core mechanistic paradigms governing their function: Asymmetric Segregation, Controlled Release, Local Translation, and Local Degradation. A comparative analysis across neurogenesis, gliogenesis, myogenesis, and mesenchymal differentiation reveals both conserved principles and lineage-specific adaptations of these mechanisms. We further review critical methodological approaches—from centrosomal proteomics to proximity ligation (BioID/APEX) and mRNA-trapping—essential for discovering CAFDs. Finally, we propose an integrative "Centriolar Decision-Making Conveyor" model, positioning this organelle as an active processing station that integrates signals and dispatches instructive cues to the nucleus. This refines our understanding of cell fate specification and highlights the therapeutic potential of manipulating centriolar signaling to direct differentiation in regenerative medicine and oncology.

For decades, centrioles were viewed as symmetrical, semi-conservatively duplicated organelles. This review synthesizes contemporary evidence to establish a fundamental paradigm shift: mother (mature) and daughter (newly formed) centrioles are intrinsically non-equivalent, serving as distinct cellular compartments with specialized roles. We systematically analyze data from super-resolution microscopy, comparative proteomics, live-cell tracking, and functional genetics to delineate a multi-layered hierarchy of asymmetry. This encompasses profound differences in ultrastructure (possession of appendages), molecular composition, functional capacity (as microtubule-organizing centers and basal bodies), dynamic properties, and fate during asymmetric cell divisions. We explore the sequential biochemical maturation program and post-translational modifications that establish this asymmetry and examine its critical manifestations across diverse cellular systems, from fibroblasts and stem cells to epithelia and sperm. Furthermore, the pathological consequences of disrupting this hierarchy are detailed, linking failures in centriole maturation to ciliopathies, neurodevelopmental disorders like microcephaly, and oncogenic processes driven by centrosomal amplification and chromosomal instability. We propose an integrative "Master-Apprentice" model, wherein the mother centriole acts as a stable organizing and signaling hub instructing its dynamic daughter counterpart. This inherent non-equivalence is not a minor detail but a core organizing principle essential for cellular polarity, accurate division, and tissue homeostasis.

Asymmetric stem cell division (ASCD) is a fundamental process for generating cellular diversity while maintaining the stem cell pool. This review synthesizes evidence from diverse model systems to establish a paradigm-shifting hypothesis: centrioles are not passive microtubule-organizing centers but active determinants that orchestrate ASCD. We argue that centrioles function as integrative hub-organelles, executing four coordinated roles: as a Compass that fixes the division axis via cortical linkages, a Dispatcher that asymmetrically recruits and segregates fate determinants, a Sensor that transduces niche signals through the primary cilium, and a Chronometer that regulates division timing. The molecular asymmetry between the mother and daughter centriole, established during interphase, is a prerequisite for correct spindle orientation and asymmetric cargo partitioning. Disruption of centriolar integrity, as seen in human "centriolopathies" like primary microcephaly and ciliopathies, leads to randomized divisions and tissue malformation. Conversely, in cancer, centrosome amplification disrupts this intrinsic asymmetry, promoting symmetric, expansive divisions of stem-like cells. This integrative model positions the centriole as the central architect of cell fate, translating extrinsic polarity into intrinsic asymmetry. Understanding this centriole-centric program opens novel avenues in regenerative medicine, by controlling differentiation in vitro, and in oncology, by targeting the self-renewal of cancer stem cells.

The adult mammalian heart is characterized by post-mitotic polyploid cardiomyocytes (CMs). Understanding how CMs regulate cell cycle exit and polyploidy can help developing new heart regenerative therapies. Here, we uncover that the PIDDosome, a multi-protein complex activating the endopeptidase Caspase-2, helps to implement a CM-specific differentiation program that limits ploidy during postnatal heart development. DNA content analyses show that cell-autonomousPIDDosomeloss causes an increase in nuclear and cellular CM ploidy. Increased ploidy does not affect cardiac structure nor function in early adulthood, but correlates with a modest reduction in cardiac performance in aged mice. PIDDosome-imposed polyploidy control commences at postnatal day 7 (P7), reaching a plateau by P14. PIDDosome activation requires ANKRD26, targeting PIDD1 to mother centrioles. Opposite to prior observations in liver development, the PIDDosome limits CM polyploidization in a p53-independent manner but reliant on induction of p21/Cdkn1a, a notion supported by nuclear RNA sequencing and genetic deletion experiments. Our results provide new insights how proliferation of polyploid CMs is restricted during postnatal heart development.

The paradox of organismal aging in the face of continuous cellular turnover remains a central question in biology. This article proposes a novel, integrative hypothesis: the non-renewed, asymmetrically inherited mother centriole in adult stem cells serves as a cumulative damage sensor and a primary driver of aging. We synthesize evidence to formulate the Centriolar Damage Accumulation Theory of Aging (CDATA). The theory posits that the biophysically stable mother centriole irreversibly accrues molecular damage (oxidative modifications, protein aggregates, loss of appendage proteins) over a lifetime. This "centriolar aging" impairs its core functions: templating the primary cilium (disrupting niche signaling) and organizing the mitotic spindle (compromising asymmetric cell division). Consequently, stem cell pools undergo exhaustion or dysfunctional expansion, leading to the failure of tissue homeostasis and the emergence of systemic aging phenotypes. We review supporting data from neural, hematopoietic, epithelial, and muscle stem cell niches, outline definitive experimental approaches for validation, discuss critiques and alternative viewpoints, and explore the profound therapeutic implications of targeting centriolar aging. This model reframes aging as a structural failure at the organelle level, offering a unified framework that connects subcellular wear to organismal decline.

Cilia are hair-like organelles that protrude from the cell surface and play vital roles in embryonic development and tissue homeostasis. Removal of centriolar coiled-coil protein 110 (CP110) from the mother centriole is a critical step in ciliogenesis, yet the underlying mechanism remains largely unknown. In this study, we identify bicaudal D cargo adaptor 2 (BICD2) as a mother centriole protein that directly binds CP110 and facilitates its removal to promote ciliogenesis. Depletion of BICD2 significantly inhibits ciliogenesis and the removal of CP110, whereas knockdown of CP110 rescues ciliogenesis defects in BICD2-deficient cells. Additionally, we show that BICD2 is recruited to the mother centriole during ciliogenesis, where it directly binds and removes CP110. Moreover, zebrafish bicd2 morphants exhibit developmental abnormalities and defective ciliogenesis, which can be reversed by reintroducing bicd2 mRNA or depleting Cp110. Our findings establish BICD2 as a key regulator of ciliogenesis through its role in CP110 removal, shedding light on the molecular mechanisms of cilia formation.

In the zebrafish left-right organizer (LRO), the Kupffer’s Vesicle (KV), cilia extend from all cells into the fluid-filled lumen, but their structural diversity and contribution to morphogenesis remain incompletely defined. We hypothesized that cilia are required for KV development and may exist in distinct structural subtypes. Using a newly engineered transgenic line (sox17:Cry2-GFP), we optogenetically disrupted the intraflagellar transport protein IFT88 in KV progenitors via blue light-induced clustering of CIB1-RFP-IFT88. This perturbation impaired ciliogenesis and disrupted lumen formation, supporting a critical role for cilia in KV morphogenesis. To assess ciliary architecture, we used volume electron microscopy (vEM) to generate a high-resolution 3D ultrastructural map of mature KVs. Only 70.1% of cilia retained both mother and daughter centrioles, suggesting centriole elimination may occur in this tissue. Among centrioles present, 33.9% had distal appendages, 91.8% had subdistal appendages, and only 5.08% exhibited rootlet fibers. Cilia were also associated with membrane-bound vesicles, including spatially biased ciliary-associated vesicles (CaVs) and dense vesicles (CaDVs). These findings demonstrate that KV cilia are structurally diverse and spatially patterned, revealing a previously unappreciated level of complexity in LRO organization and providing new insight into how ciliary specialization may contribute to left-right axis specification.

The primary cilium is a microtubule-based organelle essential for various cellular functions, particularly signal transduction. While the role of cilia in regulating signaling pathways has been extensively studied, the impact of signaling pathways on cilia formation remains less well understood. Wnt signals are critical modulators of cell fate. In this study, we investigate how modulating Wnt signaling affects cilia formation in human retinal pigment epithelial (hTERT-RPE1) cells. Our findings show that enhancement of Wnt/LRP6 signaling before serum starvation delays ciliogenesis. Cells with high baseline Wnt activity exhibited distal appendage dysregulation, failure to remove CP110-CEP97 from mother centrioles, and reduced Rab8-vesicle docking, which are critical events for cilia membrane establishment and axoneme extension. Additionally, these cells displayed reduced autophagic flux, increased mTOR kinase activity, and elevated OFD1 levels at centriolar satellites. Importantly, mTOR inhibition rescued ciliogenesis in cells with elevated Wnt activity, underscoring the interplay between these signaling pathways. Our data also indicate that insufficient Wnt signaling activation disrupts ciliogenesis, emphasizing the need for precisely regulated Wnt levels.

The trafficking, docking, and fusion of membrane vesicles at the mother centriole (MC) are required to construct the primary cilium. Here, we determined the three-dimensional (3D) membrane ultrastructures, and associated proteins, involved in primary cilium assembly upstream of axoneme growth. Our work reveals that the enlargement of small vesicles docked to the MC is a key trigger for ciliogenesis progression, a process requiring the MC distal appendage protein CEP164. We show these vesicles subsequently fuse to form tubular C-shaped and an unprecedented toroidal membrane intermediates, which ultimately organize into the ciliary vesicle covering the MC distal end. The formation of these previously uncharacterized tubular membrane ciliogenesis intermediates is orchestrated by the membrane trafficking regulators EHD1 and RAB8, and requires the IFT-B complex protein IFT88. Remarkably, we show that EHD1, through its membrane tubulation function, regulates ciliogenesis progression by directly promoting CP110/CEP97 removal from the MC cap. The establishment of these tubular membrane structures is also associated with the recruitment of the ciliary gate transition zone proteins. This study changes the architectural framework for understanding ciliogenesis mechanisms and highlights the application of isotropic ultrastructure imaging and three-dimensional quantitative analysis in understanding membrane trafficking and organelle biogenesis mechanisms.

Ciliogenesis is a highly ordered process that requires membrane trafficking, fusion, and maturation. In this study, we investigated EXOC6A, a component of the exocyst complex known for secretory vesicle trafficking and fusion, and found that it interacts with myosin-Va (Myo-Va) during ciliogenesis. EXOC6A colocalizes with Myo-Va at various stages of ciliogenesis, including preciliary vesicles, ciliary vesicles (CVs), and ciliary sheath membrane during ciliogenesis. We found that EXOC6A vesicles are actively recruited, integrated, and exit from the CVs and the ciliary sheath, implying that EXOC6A vesicles may facilitate continuous cilia membrane remodeling during ciliogenesis. Importantly, EXOC6A knockout impairs ciliogenesis, arresting most cells at the CV stage and preventing recruitment of NPHP and MKS module components to the transition zone. Furthermore, EXOC6A vesicles are transported to the mother centriole via a dynein-, microtubule-, and actin-dependent mechanism. Our results suggest that EXOC6A functions in both early and late stages of ciliogenesis and is involved in orchestrating vesicle dynamics, cilia membrane remodeling, and formation.

Introduction:Congenital anomalies of the kidney and urinary tract (CAKUT) are the leading cause of chronic kidney disease in children and young adults. Although over 50 monogenic causes have been identified, many remain unresolved. PRPF8 is a core spliceosome component, essential for pre-mRNA splicing, and further localizes to the distal mother centriole to promote ciliogenesis.Methods:We performed trio exome sequencing in 208 CAKUT families and identified strong variants in PRPF8 and the EDD-DYRK2-DDB1VprBP complex. Functional validation included splicing assays in yeast (Saccharomyces cerevisiae), Sonic hedgehog (Shh) signaling in RPE-1 cells, co-immunoprecipitation for protein complex assembly, and in situ hybridization in mouse embryos. Protein interactions were modeled using AlphaFold.Results:We identified heterozygous de novo or inherited variants in PRPF8, DYRK2, DDB1, EDD and CEP78. Yeast assays revealed that while most PRPF8 variants preserved growth and splicing at consensus splice sites, the de novo PRPF8R1681W variant impaired splicing of non-consensus splice sites and was inviable at elevated temperature. CAKUT variants failed to rescue prp28–1 and U4-cs1 alleles but showed variant-specific synthetic interactions with brr2–1, including weak suppression or synthetic sickness at elevated temperatures. Shh signaling was reduced in ~50% of PRPF8 variants expressed in RPE-1 cells. CEP78 truncating variants abrogated binding to CEP350 and VPRBP. Two DYRK2 variants disrupted EDD-DYRK2-DDB1VprBP complex formation without affecting kinase activity. In situ hybridization revealed strong Prpf8 expression in the developing collecting duct and urothelium.Conclusion:Variants in PRPF8 and components of the EDD-DYRK2-DDB1VprBP complex may contribute to CAKUT through impaired pre-mRNA splicing and defective ciliogenesis. These findings uncover an entirely new functional network of candidate genes for CAKUT and ciliopathies, significantly broadening our understanding of disease mechanisms and offering novel entry points for mechanistic studies.

Cilia are highly conserved and microtubule-based organelles protruding from the cell surface. Their assembly and growth are referred to as ciliogenesis. During ciliogenesis, the mother centriole transforms into a basal body, which serves as the template for the ciliary axoneme. Ciliary vesicles required for cilia formation are derived from the Golgi apparatus. Importantly, the physical proximity between the Golgi apparatus and the centrosome is necessary for ciliogenesis. Evidence indicates that programmed death ligand 1 (PD-L1) functions at the centrosome and Golgi apparatus. Its depletion promotes the accumulation of ciliary membrane trafficking proteins and the sensory receptor protein polycystin 2, triggering aberrant ciliogenesis and leading to the development of polycystic kidney disease (PKD). Accordingly, in this review, based on the intimate relationship between the centrosome, Golgi apparatus, and cilia, we summarize in detail the effects of centrosome and its-related proteins, Golgi apparatus and its-associated proteins and Golgi apparatus-centrosome interaction on ciliogenesis. Collectively, understanding the connection between the Golgi apparatus and centrosome provides crucial insights into ciliogenesis mechanisms. Targeting organelle interactions, especially Golgi apparatus-centrosome communication, may represent a promising therapeutic avenue for the prevention and treatment of ciliopathies.

BackgroundThe mitochondrial sheath is a defining feature of mammalian sperm with proposed functions in structural support and energy production for flagella movement. Recently, coiled coil domain containing (CCDC) protein 112 (CCDC112) was suggested to play a role in the regulation of ciliogenesis. CCDC112 is a poorly characterised protein and there is virtually no knowledge of its in vivo function.MethodsHere, we define CCDC112 as crucial for male fertility using a Ccdc112 loss-of-function mouse line. To characterize and analyze male fertility, and to identify a novel process of epididymal midpiece maturation, we utilized a range of assays including fertility testing, scanning electron microscopy, high-resolution sperm motility and power output analysis, in vitro fertilization, intracytoplasmic sperm injection, mitochondria stress test assays and glycolytic flux assays. Localization of CCDC112 in cilia was assessed via the transfection of IMCD-3 cells with a CCDC112-eGFP vector and subsequent immunofluorescent staining.ResultsResults reveal CCDC112 as a requirement for male fertility in the mouse with an essential role in mitochondrial sheath formation. Our data reveal the critical role of CCDC112 in mitochondrial morphogenesis during midpiece formation, with the lack of CCDC112 leading to significantly reduced respiration capacity, irregular flagellar waveforms, diminished progressive motility and ultimately male sterility. In the absence of CCDC112, sperm are unable to traverse the female reproductive tract to the site of fertilization and in vitro have a poor capacity to penetrate the zonae pellucidae of oocytes or fuse with the oocyte. We further unveil a previously unrecognized process of epididymal mitochondrial sheath maturation. We show the sperm midpiece is structurally immature upon exiting the testis and maturation continues during transit from the caput to the cauda epididymis. Finally, we identify CCDC112 as a component of the distal appendages of the mother centriole in IMCD-3 cells suggestive of a facilitative role for CCDC112 in protein entry into the ciliary compartment within germ cells.ConclusionCollectively, we establish CCDC112 as a key regulator of sperm midpiece assembly and function while further expanding our understanding on functional sperm production, energy generation and flagella kinematics.

Fission at endosomes is required to release cargo-laden carrier vesicles so that they can be recycled back to the plasma membrane.Actin branching plays a crucial role in the early stages of endosome fission by constricting the neck of the budding vesicle and facilitating enzyme-mediated fission.However, our understanding of how the early constriction stage and later enzyme-based stage of endosome fission are coordinated is limited, especially regarding the mechanisms of actin regulation throughout the process.We have identified a novel interaction between the human homolog of the Drosophila Nervous Wreck (Nwk) protein, known as FCH and double SH3 domains protein 2 (FCHSD2), and the endosomal scaffolding protein, MICAL-L1.We have shown that FCHSD2 is recruited to the endosome by MICAL-L1, where it is required to generate ARP2/3-mediated branched actin required for endosome fission and receptor recycling.Furthermore, MICAL-L1 also mediates the subsequent recruitment of the ATPase and fission protein EHD1 to endosomes.These findings support a model in which MICAL-L1 serves as a central coordinator of endosomal fission, linking the early actin-driven membrane remodeling to the later stages of nucleotide hydrolysis and enzymatic fission.

Primary cilia are composed of axonemal microtubules that extend from the mother centriole-derived basal body and are sheathed by the ciliary membrane. Distal appendages (DAP) of the mother centriole play crucial roles as a scaffold to initiate ciliogenesis. Although previous studies indicated that the DAP proteins CEP164 and Tau-tubulin kinase 2 (TTBK2) participate in key events of ciliogenesis, including removal of CP110 from the mother centriole and recruitment of the intraflagellar transport (IFT) machinery to the mother centriole, the overall process involving these DAP proteins remains unclear. We here established CEP164-knockout (KO) and TTBK2-KO cells, and expressed various CEP164 and TTBK2 constructs in these cells. Our results showed that the interaction of TTBK2 with CEP164 and TTBK2 kinase activity is required for the recruitment of IFT machinery components (IFT-A, IFT-B, and dynein-2 complexes) to, and removal of CP110 from the mother centriole. However, CP110 removal is not always coupled with IFT protein recruitment. Analysis using chimeric constructs of CEP164 and TTBK2 indicated that CEP164 homodimerization via its central coiled-coil region is necessary for its mother centriole localization and subsequent TTBK2 recruitment, which are required for the recruitment of IFT machinery components to the mother centriole to trigger ciliogenesis.

ABSTRACTBackgroundPrimary cilia are organelles formed on the cell surface. They can act as cellular antennae to sense signals and play important roles in various biological processes. Abnormalities in primary cilia lead to a variety of diseases collectively known as ciliopathies. Intraflagellar transport protein 20 (IFT20) has been implicated in ciliogenesis.MethodsIFT20 knockout cell lines were established using the CRISPR‐Cas9 gene editing technology. The GFP‐IFT20 plasmid was constructed with the Gateway cloning system. Protein levels were detected via immunoblotting, and the localization of IFT20, acetylated α‐tubulin, ARL13B, CP110, MKS3, IFT88, and IFT140 in wild‐type and IFT20 knockout cells was examined by immunofluorescence microscopy. The fluorescence intensities were analyzed using ImageJ. Data quantifications and mass spectrometry results were analyzed using GraphPad Prism and Metascape.ResultsThe IFT20 deficiency impaired ciliogenesis and reduced cilium length. IFT20 depletion did not affect the removal of centriolar coiled‐coil protein 110 (CP110) from the mother centriole or the recruitment of Meckel–Gruber syndrome type 3 (MKS3) to the transition zone. Mass spectrometry analysis revealed that proteins interacting with IFT20 were mainly IFT components. IFT20 knockout decreased the levels of both IFT88 and IFT140, and abrogated IFT88 localization at the basal body and ciliary axoneme. IFT20 knockout also impaired IFT140 localization at the ciliary axoneme but did not affect its localization at the basal body.ConclusionsIFT20 is involved in ciliogenesis by regulating the level and localization of other IFT proteins and may have important implications in ciliopathies and related diseases.

Pharmaceutical inhibition of the Chk2 kinase mitigates cone photoreceptor degeneration in an iPSC model of Bardet-Biedl syndrome.

Centrioles assemble and segregate in link to the cell cycle. Daughter centrioles assemble at S phase, and become young mother centrioles after M phase. Since distal appendages (DAs) are installed to young mother centrioles at the second G2/M transition phase, it takes one and a half cell cycle for a daughter centriole to fully mature into an old mother centriole. Here, we investigated specific roles of centrobin on centriole maturation by tracing its centriole localization throughout the cell cycle. Centrobin instantly places at the nascent daughter centrioles during the S phase, maintains its localization through subsequent cell cycle as these daughter centrioles mature into young mother centrioles, and detaches from the young mother centriole during the G2 phase, prior to DA installation. Centrobin KO cells exhibit two DA-installed centrioles, due to premature DA installation in daughter centrioles, and can produce doublet cilia from two DA-installed basal bodies. We also present evidence that direct phosphorylation of Plk1 is crucial for centrobin attachment to centrioles during G2 and M phases. Finally, premature DA installation was also observed in centrobin KO mice. Our results collectively demonstrate that centrobin serves as a safeguard to guide timely centriole maturation during the cell cycle.