Biology subjects

Bingle, C. D.

Publications and source records attributed to Bingle, C. D..

4 recordsLinked to original sources

bioRxiv2024

Cyclin O controls entry into the cell-cycle variant required for multiciliated cell differentiation

Multiciliated cells (MCC) ensure proper fluid circulation in various organs in metazoans. Their differentiation is marked by the massive ampliication of cilia-nucleating centrioles and is known to be controlled by various cell cycle components. Tn a companion study, we show that the differentiation of MCC is driven by a genuine cell-cycle variant characterized by sequential and wave-like expression of canonical and non-canonical cyclins such as Cyclin O (CCNO). Patients with CCNO mutations exhibit a subtype of Primary Ciliary Dyskinesia (PCD) designated as Reduced Generation of Multiple Motile Cilia (RGMC), yet the role of CCNO during MCC differentiation remains unclear. Here, using mice and human cellular models, single cell transcriptomics and functional studies, we show that Cena is activated during a strategic temporal window at the crossroads between the onset of MCC differentiation, the entry into the MCC cell cycle variant, and the activation of the centriole biogenesis program. We ind that the absence of Cena leads to a block of MCC progenitor differentiation at the G1/S-like transition, just before the beginning of centriole formation. This leads to a complete lack of centrioles and cilia in mouse brain and human airway MCC. Altogether, our study identifies CCNO as a core regulator of entry into the MCC cell cycle variant and shows that the coupling of centriole biogenesis to an S-like phase, maintained in MCC, is dependent on CCNO. One sentence summaryCyclin O is necessary for multiciliated cells to enter their differentiation cell cycle variant and allows the massive amplification of centrioles, which serve as basal bodies for cilia nucleation.

cell biology↗

bioRxiv2020

Expression and function of murine WFDC2 in the respiratory tract.

WFDC2/HE4 encodes a poorly characterised secretory protein that shares structural similarity with multifunctional host defence proteins through possession of two conserved Whey Acidic Protein/four disulphide-core (WFDC) domains. WFDC2 is expressed in multiple epithelia and although its function remains unresolved, it is also overexpressed in a number of human cancers and has an established role as a cancer marker. Currently, little is known about the distribution of WFDC2 in the mouse and thus we have systematically analysed the mouse wfdc2 gene, its expression and distribution. We have used recombinant WFDC2 for functional studies. Wfdc2 is the most highly expressed family member in the lung and is enriched in the nasopharynx. Wfdc2 is the most highly expressed family member in differentiated epithelial cells isolated from the trachea, nasal passages and middle ear. Wfdc2 consists of 5 exons with exon 3 encoding an unstructured linker region that separates the two WFDC domains. This genomic organisation appears to be restricted to the Muridae and Cricetidae families of rodents. Similar to the situation in man, mouse wfdc2 can be alternatively spliced to yield a number of distinct transcripts that have the potential to generate a repertoire of distinct protein isoforms. We used immunohistochemistry to localise the proteins to tissues of the respiratory tract and head and neck regions. Although the protein was limited to epithelial cells of the respiratory tract and nasal and oral cavities, it was expressed in different cells in different regions suggesting expression is governed by a unique regulatory mechanism. Recombinant WFDC2 did not possess antiproteinase activity against trypsin or elastase and had no clear antimicrobial activity.

genomics↗

bioRxiv2019

The transcriptional landscape of the murine middle ear epithelium in vitro

Otitis media (OM) is the most common paediatric disease and leads to significant morbidity. Although understanding of underlying disease mechanisms is hampered by complex pathophysiology, it is clear that epithelial abnormalities underpin the disease. The mechanisms underpinning epithelial remodelling in OM remain unclear. We recently described a novel in vitro model of mouse middle ear epithelial cells (mMEECs) that undergoes mucociliary differentiation into the varied epithelial cell populations seen in the middle ear cavity. We now describe genome wide gene expression profiles of mMEECs as they undergo differentiation. We compared the gene expression profiles of original (uncultured) middle ear cells, confluent cultures of undifferentiated cells (day 0 of ALI) and cells that had been differentiated for 7 days at an ALI. >5000 genes were differentially expressed among the three groups of cells. Approximately 4000 genes were differentially expressed between the original cells and day 0 of ALI culture. The original cell population was shown to contain a mix of cell types, including contaminating inflammatory cells that were lost on culture. Approximately 500 genes were upregulated during ALI induced differentiation. These included some secretory genes and some enzymes but most were associated with the process of ciliogenesis. Our in vitro model of differentiated murine middle ear epithelium exhibits a transcriptional profile consistent with the mucociliary epithelium seen within the middle ear. Knowledge of the transcriptional landscape of this epithelium will provide a basis for understanding the phenotypic changes seen in murine models of OM.

genomics↗

bioRxiv2018

Mcidas mutant mice reveal a two-step process for the specification and differentiation of multiciliated cells in mammals

Motile cilia on multiciliated cells (MCCs) function in fluid clearance over epithelia. Studies with Xenopus embryos and patients with the congenital respiratory disorder reduced generation of multiple motile cilia, have implicated the nuclear protein MCIDAS (MCI), in the transcriptional regulation of MCC specification and differentiation. Recently, a paralogous protein, GMNC, was also shown to be required for MCC formation. Surprisingly, and in contrast to the presently held view, we find that Mci mutant mice can specify MCC precursors. However, these precursors cannot produce multiple basal bodies, and mature into single ciliated cells. We show that MCI is required specifically to induce deuterosome pathway components for the production of multiple basal bodies. Moreover, GMNC and MCI associate differentially with the cell-cycle regulators E2F4 and E2F5, which enables them to activate distinct sets of target genes (ciliary transcription factor genes versus genes for basal body generation). Our data establish a previously unrecognized two-step model for MCC development: GMNC functions in the initial step for MCC precursor specification. GMNC induces Mci expression, which then drives the second step of basal body production for multiciliation.\n\nSUMMARY STATEMENTWe show how two GEMININ family proteins function in mammalian multiciliated cell development: GMNC regulates precursor specification and MCIDAS induces multiple basal body formation for multiciliation.

developmental biology↗