scholarly journals Cep120 is asymmetrically localized to the daughter centriole and is essential for centriole assembly

2010 ◽  
Vol 191 (2) ◽  
pp. 331-346 ◽  
Author(s):  
Moe R. Mahjoub ◽  
Zhigang Xie ◽  
Tim Stearns
Keyword(s):  
Basal Bodies ◽  
Animal Cells ◽  
Tracheal Epithelial Cells ◽  
Centriole Duplication ◽  
Photobleaching Recovery ◽  
Mother And Daughter ◽  
Tracheal Epithelial ◽  
Centriole Assembly ◽  
And Function ◽  
Daughter Centriole

Centrioles form the core of the centrosome in animal cells and function as basal bodies that nucleate and anchor cilia at the plasma membrane. In this paper, we report that Cep120 (Ccdc100), a protein previously shown to be involved in maintaining the neural progenitor pool in mouse brain, is associated with centriole structure and function. Cep120 is up-regulated sevenfold during differentiation of mouse tracheal epithelial cells (MTECs) and localizes to basal bodies. Cep120 localizes preferentially to the daughter centriole in cycling cells, and this asymmetry between mother and daughter centrioles is relieved coincident with new centriole assembly. Photobleaching recovery analysis identifies two pools of Cep120, differing in their halftime at the centriole. We find that Cep120 is required for centriole duplication in cycling cells, centriole amplification in MTECs, and centriole overduplication in S phase–arrested cells. We propose that Cep120 is required for centriole assembly and that the observed defect in neuronal migration might derive from a defect in this process.

scholarly journals Molecular characterization of centriole assembly in ciliated epithelial cells

2007 ◽  
Vol 178 (1) ◽  
pp. 31-42 ◽  
Author(s):  
Eszter K. Vladar ◽  
Tim Stearns
Keyword(s):  
Epithelial Cells ◽  
Mammalian Cells ◽  
Intraflagellar Transport ◽  
Proximal Region ◽  
Basal Bodies ◽  
Tracheal Epithelial Cells ◽  
Centriole Duplication ◽  
Centriole Assembly ◽  
Ciliated Epithelial Cells ◽  
Centrosomal Proteins

Ciliated epithelial cells have the unique ability to generate hundreds of centrioles during differentiation. We used centrosomal proteins as molecular markers in cultured mouse tracheal epithelial cells to understand this process. Most centrosomal proteins were up-regulated early in ciliogenesis, initially appearing in cytoplasmic foci and then incorporated into centrioles. Three candidate proteins were further characterized. The centrosomal component SAS-6 localized to basal bodies and the proximal region of the ciliary axoneme, and depletion of SAS-6 prevented centriole assembly. The intraflagellar transport component polaris localized to nascent centrioles before incorporation into cilia, and depletion of polaris blocked axoneme formation. The centriolar satellite component PCM-1 colocalized with centrosomal components in cytoplasmic granules surrounding nascent centrioles. Interfering with PCM-1 reduced the amount of centrosomal proteins at basal bodies but did not prevent centriole assembly. This system will help determine the mechanism of centriole formation in mammalian cells and how the limitation on centriole duplication is overcome in ciliated epithelial cells.

scholarly journals Discovery of Alstrom syndrome gene as a regulator of centrosome duplication in asymmetrically dividing stem cells in Drosophila.: Supplementary table-mass spectrometry

2018 ◽  
Author(s):  
Cuie Chen ◽  
Yukiko Yamashita
Keyword(s):  
Stem Cells ◽  
Molecular Mechanisms ◽  
Germline Stem Cells ◽  
Causative Gene ◽  
Centriole Duplication ◽  
Alström Syndrome ◽  
Mother And Daughter ◽  
Dividing Cells ◽  
Alstrom Syndrome ◽  
Daughter Centriole

Stereotypical inheritance of the mother vs. daughter centrosomes has been reported in several stem cells that divide asymmetrically. We report the identification of a protein that exhibits asymmetric localization between mother and daughter centrosomes in asymmetrically dividing Drosophila male germline stem cells (GSCs). We show that Alms1a, a Drosophila homolog of the causative gene for the human ciliopathy Alstrom Syndrome, is a ubiquitous mother centriole protein with a unique additional localization to the daughter centriole only in the mother centrosome of GSCs. Depletion of alms1a results in rapid loss of centrosomes due to failure in daughter centriole duplication. We reveal that alms1a is specifically required for centriole duplication in asymmetrically dividing cells but not in symmetrically dividing differentiating cells in multiple stem cell lineages. The unique requirement of alms1a in asymmetric dividing cells may shed light onto the molecular mechanisms of Alstrom syndrome pathogenesis.

scholarly journals Identification of contractile proteins in basal bodies of ciliated tracheal epithelial cells.

1980 ◽  
Vol 28 (11) ◽  
pp. 1189-1197 ◽  
Author(s):  
R E Gordon ◽  
B P Lane ◽  
F Miller
Keyword(s):  
Basal Body ◽  
Contractile Function ◽  
Ultrastructural Localization ◽  
Immunoperoxidase Technique ◽  
Basal Bodies ◽  
Tracheal Epithelial Cells ◽  
Tracheal Epithelial ◽  
Indirect Immunoperoxidase ◽  
Basal Foot ◽  
Basal Density

To determine the molecular composition of the components of basal bodies and the interbasal body apparatus of ciliated cells in rat tracheal epithelium, we used rabbit anti-actin, anti-alpha-actinin, anti-tropomyosin, and anti-myosin as primary antisera applied to the tissue in an indirect immunoperoxidase technique. The antisera was proven to be monospecific by elution of antibody after affinity chromatography. Sheep anti-rabbit immunoglobulin Fab fragments coupled to peroxidase were used for ultrastructural localization of the bound rabbit antibody. Antibodies against alpha-actinin were demonstrated around peripheral microtubules of cilia and linking these microtubules to central doublet and plasma membrane. Alpha-actinin was also shown in the basal foot processes. Anti-actin antibodies were associated with microtubules of the cilium and basal bodies, except in the region of the ciliary necklace. The antibodies directed against actin also had affinity for rootlets, basal foot processes, and communications between basal bodies and foot processes. Both anti-myosin and anti-tropomyosin antibodies were localized to part of the region of the constriction of the cilium, to the central basal density and the outer surfaces of basal body microtubules, and to the basal foot processes together with their communications to the basal body. The data suggest active contractile function of basal bodies.

scholarly journals Mitotic Regulators Govern Progress through Steps in the Centrosome Duplication Cycle

1999 ◽  
Vol 147 (7) ◽  
pp. 1371-1378 ◽  
Author(s):  
Smruti J. Vidwans ◽  
Mei Lie Wong ◽  
Patrick H. O'Farrell
Keyword(s):  
Cell Cycle ◽  
Centrosome Duplication ◽  
Mother And Daughter ◽  
Centriole Assembly ◽  
Duplication Cycle ◽  
Daughter Centriole ◽  
Drosophila Embryos

Centrosome duplication is marked by discrete changes in centriole structure that occur in lockstep with cell cycle transitions. We show that mitotic regulators govern steps in centriole replication in Drosophila embryos. Cdc25string, the expression of which initiates mitosis, is required for completion of daughter centriole assembly. Cdc20fizzy, which is required for the metaphase-anaphase transition, is required for timely disengagement of mother and daughter centrioles. Stabilization of mitotic cyclins, which prevents exit from mitosis, blocks assembly of new daughter centrioles. Common regulation of the nuclear and centrosome cycles by mitotic regulators may ensure precise duplication of the centrosome.

scholarly journals Sas-4 proteins are required during basal body duplication in Paramecium

2011 ◽  
Vol 22 (7) ◽  
pp. 1035-1044 ◽  
Author(s):  
Delphine Gogendeau ◽  
Ilse Hurbain ◽  
Graca Raposo ◽  
Jean Cohen ◽  
France Koll ◽  
...  
Keyword(s):  
Caenorhabditis Elegans ◽  
Basal Body ◽  
Basal Bodies ◽  
Paramecium Tetraurelia ◽  
Animal Cells ◽  
Centriole Duplication ◽  
Specific Order ◽  
In Cells

Centrioles and basal bodies are structurally related organelles composed of nine microtubule (MT) triplets. Studies performed in Caenorhabditis elegans embryos have shown that centriole duplication takes place in sequential way, in which different proteins are recruited in a specific order to assemble a procentriole. ZYG-1 initiates centriole duplication by triggering the recruitment of a complex of SAS-5 and SAS-6, which then recruits the final player, SAS-4, to allow the incorporation of MT singlets. It is thought that a similar mechanism (that also involves additional proteins) is present in other animal cells, but it remains to be investigated whether the same players and their ascribed functions are conserved during basal body duplication in cells that exclusively contain basal bodies. To investigate this question, we have used the multiciliated protist Paramecium tetraurelia. Here we show that in the absence of PtSas4, two types of defects in basal body duplication can be identified. In the majority of cases, the germinative disk and cartwheel, the first structures assembled during duplication, are not detected. In addition, if daughter basal bodies were formed, they invariably had defects in MT recruitment. Our results suggest that PtSas4 has a broader function than its animal orthologues.

scholarly journals Bacterial Exposure Induces and Activates Matrilysin in Mucosal Epithelial Cells

2000 ◽  
Vol 148 (6) ◽  
pp. 1305-1315 ◽  
Author(s):  
Yolanda S. López-Boado ◽  
Carole L. Wilson ◽  
Lora V. Hooper ◽  
Jeffrey I. Gordon ◽  
Scott J. Hultgren ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Acute Infection ◽  
Human Colon ◽  
Cell Types ◽  
The Body ◽  
Apical Surface ◽  
Tracheal Epithelial Cells ◽  
Lung Carcinoma Cells ◽  
Tracheal Epithelial ◽  
And Function

Matrilysin, a matrix metalloproteinase, is expressed and secreted lumenally by intact mucosal and glandular epithelia throughout the body, suggesting that its regulation and function are shared among tissues. Because matrilysin is produced in Paneth cells of the murine small intestine, where it participates in innate host defense by activation of prodefensins, we speculated that its expression would be influenced by bacterial exposure. Indeed, acute infection (10–90 min) of human colon, bladder, and lung carcinoma cells, primary human tracheal epithelial cells, and human tracheal explants with type 1–piliated Escherichia coli mediated a marked (25–50-fold) and sustained (>24 h) induction of matrilysin production. In addition, bacterial infection resulted in activation of the zymogen form of the enzyme, which was selectively released at the apical surface. Induction of matrilysin was mediated by a soluble, non-LPS bacterial factor and correlated with the release of defensin-like bacteriocidal activity. Bacteria did not induce matrilysin in other cell types, and expression of other metalloproteinases by epithelial cells was not affected by bacteria. Matrilysin was not detected in germ-free mice, but the enzyme was induced after colonization with Bacteroides thetaiotaomicron. These findings indicate that bacterial exposure is a potent and physiologically relevant signal regulating matrilysin expression in epithelial cells.

scholarly journals Daughter centrioles assemble preferentially towards the nuclear envelope in Drosophila syncytial embryos

2021 ◽  
Author(s):  
Neil Henry James Cunningham ◽  
Imene Bouhlel ◽  
Paul Thomas Conduit
Keyword(s):  
Nuclear Envelope ◽  
Single Mother ◽  
S Phase ◽  
Animal Cells ◽  
Simultaneous Formation ◽  
Centriole Duplication ◽  
External Cues ◽  
Mother Centriole ◽  
Pericentriolar Material ◽  
Daughter Centriole

Centrosomes are important organisers of microtubules within animal cells. They comprise a pair of centrioles surrounded by the pericentriolar material (PCM), which nucleates and organises the microtubules. To maintain centrosome numbers, centrioles must duplicate once and only once per cell cycle. During S-phase, a single new daughter centriole is built orthogonally on one side of each radially symmetric mother centriole. Mis-regulation of duplication can result in the simultaneous formation of multiple daughter centrioles around a single mother centriole, leading to centrosome amplification, a hallmark of cancer. It remains unclear how a single duplication site is established. It also remains unknown whether this site is pre-defined or randomly positioned around the mother centriole. Here, we show that within Drosophila syncytial embryos daughter centrioles preferentially assemble on the side of the mother facing the nuclear envelope, to which the centrosomes are closely attached. This positional preference is established early during duplication and remains stable throughout daughter centriole assembly, but is lost in centrosomes forced to lose their connection to the nuclear envelope. This shows that non-centrosomal cues influence centriole duplication and raises the possibility that these external cues could help establish a single duplication site.

scholarly journals The centriole duplication cycle

2014 ◽  
Vol 369 (1650) ◽  
pp. 20130460 ◽  
Author(s):  
Elif Nur Fırat-Karalar ◽  
Tim Stearns
Keyword(s):  
Cell Cycle ◽  
Cell Polarization ◽  
Brain Diseases ◽  
Basal Bodies ◽  
Animal Cells ◽  
Centriole Duplication ◽  
Pericentriolar Material ◽  
Cilia And Flagella ◽  
Duplication Cycle ◽  
Lower Plant

Centrosomes are the main microtubule-organizing centre of animal cells and are important for many critical cellular and developmental processes from cell polarization to cell division. At the core of the centrosome are centrioles, which recruit pericentriolar material to form the centrosome and act as basal bodies to nucleate formation of cilia and flagella. Defects in centriole structure, function and number are associated with a variety of human diseases, including cancer, brain diseases and ciliopathies. In this review, we discuss recent advances in our understanding of how new centrioles are assembled and how centriole number is controlled. We propose a general model for centriole duplication control in which cooperative binding of duplication factors defines a centriole ‘origin of duplication’ that initiates duplication, and passage through mitosis effects changes that license the centriole for a new round of duplication in the next cell cycle. We also focus on variations on the general theme in which many centrioles are created in a single cell cycle, including the specialized structures associated with these variations, the deuterosome in animal cells and the blepharoplast in lower plant cells.

Effect of hormones on growth and function of cultured canine tracheal epithelial cells

1988 ◽  
Vol 255 (2) ◽  
pp. C237-C245 ◽  
Author(s):  
M. R. Van Scott ◽  
N. P. Lee ◽  
J. R. Yankaskas ◽  
R. C. Boucher
Keyword(s):  
Ion Transport ◽  
Morphological Differentiation ◽  
Acute Effect ◽  
Adrenergic Stimulation ◽  
Collagen Matrices ◽  
Tracheal Epithelial Cells ◽  
Growth Supplement ◽  
Tracheal Epithelial ◽  
Cellular Responsiveness ◽  
And Function

Insulin (INS), endothelial cell growth supplement (ECGS), transferrin (TF), cholera toxin (CT), hydrocortisone (HC), triiodothyronine (T3), and epidermal growth factor (EGF) were systematically examined for their effects on proliferation, ion transport activity, and morphological differentiation of canine tracheal epithelial (CTE) cells in culture. INS, ECGS, TF, and CT increase proliferation of CTE cells cultured on plastic Petri dishes but exhibit no acute effect on the bioelectric activity of freshly excised CTE. CT increases amiloride-insensitive transepithelial ion transport across both freshly excised canine trachea and CTE cultures. EGF has no effect on proliferation of CTE cells on plastic but induces hyperplasia of CTE cells on collagen matrices. EGF does not alter basal transepithelial ion transport across cultures but increases cellular responsiveness to beta-adrenergic stimulation. HC and T3 have no effect on proliferation or transepithelial bioelectric properties of CTE cells but improve morphological differentiation yielding cultures of complex epithelia containing cuboidal ciliated and nonciliated cells. These results demonstrate that growth and function of cultured CTE cells are affected by specific growth factors.

scholarly journals A molecular mechanism for the procentriole recruitment of Ana2

2019 ◽  
Author(s):  
Tiffany A. McLamarrah ◽  
Sarah K. Speed ◽  
Daniel W. Buster ◽  
Carey J. Fagerstrom ◽  
Brian J. Galletta ◽  
...  
Keyword(s):  
Molecular Mechanism ◽  
Kinase Activity ◽  
Surface Protein ◽  
Single Site ◽  
Centriole Duplication ◽  
C Terminus ◽  
N Terminus ◽  
Mother Centriole ◽  
Centriole Assembly ◽  
Daughter Centriole

AbstractCentriole duplication begins with the assembly of a pre-procentriole at a single site on a mother centriole and proceeds with the hierarchical recruitment of a conserved set of proteins, including Polo-like kinase 4 (Plk4)/ZYG-1, Ana2/SAS-5/STIL, and the cartwheel protein Sas6. During assembly, Ana2/STIL stimulates Plk4 kinase activity, and in turn, Ana2/STIL’s C-terminus is phosphorylated, allowing it to bind and recruit Sas6. The assembly steps immediately preceding Sas6-loading appear clear, but the mechanism underlying the upstream pre-procentriole recruitment of Ana2/STIL is not. In contrast to proposed models of Ana2/STIL recruitment, we recently showed that Drosophila Ana2 targets procentrioles independent of Plk4-binding. Instead, Ana2 recruitment requires Plk4 phosphorylation of Ana2’s N-terminus, but the mechanism explaining this process is unknown. Here, we show that the amyloid-like domain of Sas4, a centriole surface protein, binds Plk4 and Ana2, and facilitates phosphorylation of Ana2’s N-terminus which increases Ana2’s affinity for Sas4. Consequently, Ana2 accumulates at the procentriole to induce daughter centriole assembly.

Sign in / Sign up

Export Citation Format

Share Document