bims-bicyki 2023-06-18 papers

bims-bicyki

Biomed News

on Bicaudal-C1 and interactors in cystic kidney disease

Issue of 2023–06–18
eightteen papers selected by
Céline Gagnieux, École Polytechnique Fédérale de Lausanne

Cardiovascular perspectives of the TRP channel polycystin 2.
Regulation of the length of neuronal primary cilia and its potential effects on signalling.
Cystin is required for maintaining fibrocystin (FPC) levels and safeguarding proteome integrity in mouse renal epithelial cells: A mechanistic connection between the kidney defects in cpk mice and human ARPKD: A mechanistic connection between the kidney defects in cpk mice and human ARPKD.
Shortening of primary cilia length is associated with urine concentration in the kidneys.
Primary cilia of the kidney: from ciliopathy to urinary concentration.
Targeting the ADPKD methylome using nanoparticle-mediated combination therapy.
Possible Hepatic Torsion, a Pediatric Patient With Polycystic Kidney Disease.
Regulation of Primary Cilium Length by O-GlcNAc during Neuronal Development in a Human Neuron Model.
Investigations on Primary Cilia of Nthy-ori 3-1 Cells upon Cysteine Cathepsin Inhibition or Thyrotropin Stimulation.
Oral-facio-digital syndrome type I: In the differential diagnosis of autosomic dominant polycystic kidney disease, about three cases.
A phylogenetic profiling approach identifies novel ciliogenesis genes in Drosophila and C. elegans.
IFT74 variants cause skeletal ciliopathy and motile cilia defects in mice and humans.
Dynein-2-driven intraciliary retrograde trafficking indirectly requires multiple interactions of IFT54 in the IFT-B complex with the dynein-2 complex.
Diet and Physical Activity in Adult Dominant Polycystic Kidney Disease: A Review of the Literature.
LRRC6 regulates biogenesis of motile cilia by aiding FOXJ1 translocation into the nucleus.
The Caenorhabditis elegans Shugoshin regulates TAC-1 in cilia.
Robust acoustic trapping and perturbation of single-cell microswimmers illuminate three-dimensional swimming and ciliary coordination.
Primary Ciliary Dyskinesia Patient-Specific hiPSC-Derived Airway Epithelium in Air-Liquid Interface Culture Recapitulates Disease Specific Phenotypes In Vitro.

J Physiol. 2023 Jun 13.

Cardiovascular perspectives of the TRP channel polycystin 2.

Karla M Márquez-Nogueras, Ivana Y Kuo.

  Calcium release from the endoplasmic reticulum is predominantly driven by two key ion channel receptors, Inositol 1, 4, 5-triphosphate receptor (InsP3 R) in non-excitable cells and Ryanodine Receptor (RyR) in excitable and muscle-based cells. These calcium transients can be modified by other less-studied ion channels, including polycystin 2 (PC2), a member of the Transient Receptor Potential (TRP) family. PC2 is found in various cell types and is evolutionarily conserved with paralogs ranging from single-cell organisms to yeasts and mammals. Interest in the mammalian form of PC2 stems from its disease relevance, as mutations in the PKD2 gene, which encodes PC2, result in Autosomal Dominant Polycystic Kidney Disease (ADPKD). This disease is characterized by renal and liver cysts, and cardiovascular extrarenal manifestations. However, in contrast to the well-defined roles of many TRP channels, the role of PC2 remains unknown, as it has different subcellular locations, and the functional understanding of the channel in each location is still unclear. Recent structural and functional studies have shed light on this channel. Moreover, studies on cardiovascular tissues have demonstrated a diverse role of PC2 in these tissues compared to that in the kidney. We highlight recent advances in understanding the role of this channel in the cardiovascular system and discuss the functional relevance of PC2 in non-renal cells. Abstract figure legend The Transient Receptor Potential (TRP) channel polycystin 2 (PC2) allows for cation flux in a variety of subcellular locations including the primary cilia, plasma membrane and endoplasmic reticulum, ultimately contributing to cardiac and vascular contractility. This article is protected by copyright. All rights reserved.

Keywords:  Calcium; Cardiac; Polycystin; TRP channels; vasculature

DOI:  https://doi.org/10.1113/JP283835
Trends Cell Biol. 2023 Jun 09. pii: S0962-8924(23)00088-0. [Epub ahead of print]

Regulation of the length of neuronal primary cilia and its potential effects on signalling.

Viviana Macarelli, Eleni Leventea, Florian T Merkle.

  Primary cilia protrude from most vertebrate cell bodies and act as specialized 'signalling antennae' that can substantially lengthen or retract in minutes to hours in response to specific stimuli. Here, we review the conditions and mechanisms responsible for regulating primary cilia length (PCL) in mammalian nonsensory neurons, and propose four models of how they could affect ciliary signalling and alter cell state and suggest experiments to distinguish between them. These models include (i) the passive indicator model, where changes in PCL have no consequence; (ii) the rheostat model, in which a longer cilium enhances signalling; (iii) the local concentration model, where ciliary shortening increases the local protein concentration to facilitate signalling; and (iv) the altered composition model where changes in PCL skew signalling.

Keywords:  GPCR; length changes; molecular concentration; primary cilia; signal transduction

DOI:  https://doi.org/10.1016/j.tcb.2023.05.005
FASEB J. 2023 Jul;37(7): e23008

Cystin is required for maintaining fibrocystin (FPC) levels and safeguarding proteome integrity in mouse renal epithelial cells: A mechanistic connection between the kidney defects in cpk mice and human ARPKD: A mechanistic connection between the kidney defects in cpk mice and human ARPKD.

Yiming J Zhang, Chaozhe Yang, Wei Wang, Naoe Harafuji, Piotr Stasiak, P Darwin Bell, Ljubica Caldovic, Elizabeth Sztul, Lisa M Guay-Woodford, Zsuzsanna Bebok.

  Autosomal recessive polycystic kidney disease (ARPKD) is caused primarily by mutations in PKHD1, encoding fibrocystin (FPC), but Pkhd1 mutant mice failed to reproduce the human phenotype. In contrast, the renal lesion in congenital polycystic kidney (cpk) mice, with a mutation in Cys1 and cystin protein loss, closely phenocopies ARPKD. Although the nonhomologous mutation diminished the translational relevance of the cpk model, recent identification of patients with CYS1 mutations and ARPKD prompted the investigations described herein. We examined cystin and FPC expression in mouse models (cpk, rescued-cpk (r-cpk), Pkhd1 mutants) and mouse cortical collecting duct (CCD) cell lines (wild type (wt), cpk). We found that cystin deficiency caused FPC loss in both cpk kidneys and CCD cells. FPC levels increased in r-cpk kidneys and siRNA of Cys1 in wt cells reduced FPC. However, FPC deficiency in Pkhd1 mutants did not affect cystin levels. Cystin deficiency and associated FPC loss impacted the architecture of the primary cilium, but not ciliogenesis. No reduction in Pkhd1 mRNA levels in cpk kidneys and CCD cells suggested posttranslational FPC loss. Studies of cellular protein degradation systems suggested selective autophagy as a mechanism. In support of the previously described function of FPC in E3 ubiquitin ligase complexes, we demonstrated reduced polyubiquitination and elevated levels of functional epithelial sodium channel in cpk cells. Therefore, our studies expand the function of cystin in mice to include inhibition of Myc expression via interaction with necdin and maintenance of FPC as functional component of the NEDD4 E3 ligase complexes. Loss of FPC from E3 ligases may alter the cellular proteome, contributing to cystogenesis through multiple, yet to be defined, mechanisms.

Keywords:   cpk ; ARPKD; FPC; cystin; proteome; selective autophagy

DOI:  https://doi.org/10.1096/fj.202300100R
Kidney Res Clin Pract. 2023 May;42(3): 312-324

Shortening of primary cilia length is associated with urine concentration in the kidneys.

Min Jung Kong, Sang Jun Han, Sung Young Seu, Ki-Hwan Han, Joshua H Lipschutz, Kwon Moo Park.

   BACKGROUND: The primary cilium, a microtubule-based cellular organelle present in certain kidney cells, functions as a mechano-sensor to monitor fluid flow in addition to various other biological functions. In kidneys, the primary cilia protrude into the tubular lumen and are directly exposed to pro-urine flow and components. However, their effects on urine concentration remain to be defined. Here, we investigated the association between primary cilia and urine concentration.
METHODS: Mice either had free access to water (normal water intake, NWI) or were not allowed access to water (water deprivation, WD). Some mice received tubastatin, an inhibitor of histone deacetylase 6 (HDAC6), which regulates the acetylation of α-tubulin, a core protein of microtubules.
RESULTS: WD decreased urine output and increased urine osmolality, concomitant with apical plasma membrane localization of aquaporin 2 (AQP2) in the kidney. After WD, compared with after NWI, the lengths of primary cilia in renal tubular epithelial cells were shortened and HDAC6 activity increased. WD induced deacetylation of α-tubulin without altering α-tubulin levels in the kidney. Tubastatin prevented the shortening of cilia through increasing HDAC6 activity and consequently increasing acetylated α-tubulin expression. Furthermore, tubastatin prevented the WD-induced reduction of urine output, urine osmolality increase, and apical plasma membrane localization of AQP2.
CONCLUSIONS: WD shortens primary cilia length through HDAC6 activation and α-tubulin deacetylation, while HDAC6 inhibition blocks the WD-induced changes in cilia length and urine output. This suggests that cilia length alterations are involved, at least in part, in the regulation of body water balance and urine concentration.

Keywords:  Aquaporin 2; Histone deacetylase 6; Osmolality; Primary cilia; Water deprivation

DOI:  https://doi.org/10.23876/j.krcp.22.274
Kidney Res Clin Pract. 2023 May;42(3): 279-281

Primary cilia of the kidney: from ciliopathy to urinary concentration.

Gheun-Ho Kim.

DOI: https://doi.org/10.23876/j.krcp.23.083
APL Bioeng. 2023 Jun;7(2): 026111

Targeting the ADPKD methylome using nanoparticle-mediated combination therapy.

Annie Trinh, Yi Huang, Hanjuan Shao, Aparna Ram, Julien Morival, Jonathan Wang, Eun Ji Chung, Timothy L Downing.

DNA methylation aberrancies are found in autosomal dominant polycystic kidney disease (ADPKD), which suggests the methylome to be a promising therapeutic target. However, the impact of combining DNA methylation inhibitors (DNMTi) and ADPKD drugs in treating ADPKD and on disease-associated methylation patterns has not been fully explored. To test this, ADPKD drugs, metformin and tolvaptan (MT), were delivered in combination with DNMTi 5-aza-2'-deoxycytidine (Aza) to 2D or 3D cystic Pkd1 heterozygous renal epithelial cells (PKD1-Het cells) as free drugs or within nanoparticles to enable direct delivery for future in vivo applications. We found Aza synergizes with MT to reduce cell viability and cystic growth. Reduced representation bisulfite sequencing (RRBS) was performed across four groups: PBS, Free-Aza (Aza), Free-Aza+MT (F-MTAza), and Nanoparticle-Aza+MT (NP-MTAza). Global methylation patterns showed that while Aza alone induces a unimodal intermediate methylation landscape, Aza+MT recovers the bimodality reminiscent of somatic methylomes. Importantly, site-specific methylation changes associated with F-MTAza and NP-MTAza were largely conserved including hypomethylation at ADPKD-associated genes. Notably, we report hypomethylation of cancer-associated genes implicated in ADPKD pathogenesis as well as new target genes that may provide additional therapeutic effects. Overall, this study motivates future work to further elucidate the regulatory mechanisms of observed drug synergy and apply these combination therapies in vivo.

DOI: https://doi.org/10.1063/5.0151408
Clin Pediatr (Phila). 2023 Jun 13. 99228231180180

Possible Hepatic Torsion, a Pediatric Patient With Polycystic Kidney Disease.

Caitlin M Diefendorf, Andrew S Phelps, Henry C Lin.

DOI: https://doi.org/10.1177/00099228231180180
Cells. 2023 May 31. pii: 1520. [Epub ahead of print]12(11):

Regulation of Primary Cilium Length by O-GlcNAc during Neuronal Development in a Human Neuron Model.

Jie L Tian, Chia-Wei Huang, Farzad Eslami, Michael Philip Mannino, Rebecca Lee Mai, Gerald W Hart.

  The primary cilium plays critical roles in the homeostasis and development of neurons. Recent studies demonstrate that cilium length is regulated by the metabolic state of cells, as dictated by processes such as glucose flux and O-GlcNAcylation (OGN). The study of cilium length regulation during neuron development, however, has been an area left largely unexplored. This project aims to elucidate the roles of O-GlcNAc in neuronal development through its regulation of the primary cilium. Here, we present findings suggesting that OGN levels negatively regulate cilium length on differentiated cortical neurons derived from human-induced pluripotent stem cells. In neurons, cilium length increased significantly during maturation (after day 35), while OGN levels began to drop. Long-term perturbation of OGN via drugs, which inhibit or promote its cycling, during neuron development also have varying effects. Diminishing OGN levels increases cilium length until day 25, when neural stem cells expand and undergo early neurogenesis, before causing cell cycle exit defects and multinucleation. Elevating OGN levels induces greater primary cilia assembly but ultimately results in the development of premature neurons, which have higher insulin sensitivity. These results indicate that OGN levels and primary cilium length are jointly critical in proper neuron development and function. Understanding the interplays between these two nutrient sensors, O-GlcNAc and the primary cilium, during neuron development is important in paving connections between dysfunctional nutrient-sensing and early neurological disorders.

Keywords:  O-GlcNAc; cortical neurons; human induced-pluripotent stem cells; neuronal development; primary cilia

DOI:  https://doi.org/10.3390/cells12111520
Int J Mol Sci. 2023 May 26. pii: 9292. [Epub ahead of print]24(11):

Investigations on Primary Cilia of Nthy-ori 3-1 Cells upon Cysteine Cathepsin Inhibition or Thyrotropin Stimulation.

Alara Gaye Doğru, Maren Rehders, Klaudia Brix.

  In the thyroid gland, cysteine cathepsins are secreted upon thyrotropin stimulation for thyroglobulin processing, and they are present at the primary cilia of thyroid epithelial cells. Treatment with protease inhibitors resulted in the loss of cilia from rodent thyrocytes and caused redistribution of the thyroid co-regulating G protein-coupled receptor Taar1 to the endoplasmic reticulum. These findings suggest that ciliary cysteine cathepsins are important to maintain sensory and signaling properties for the proper regulation and homeostasis of thyroid follicles. Therefore, it is important to better understand how cilia structure and frequencies are maintained in human thyroid epithelial cells. Hence, we aimed to investigate the potential role of cysteine cathepsins for the maintenance of primary cilia in the normal human Nthy-ori 3-1 thyroid cell line. This was approached by determining cilia lengths and frequencies in cysteine peptidase inhibition conditions in Nthy-ori 3-1 cell cultures. Cilia lengths were shortened upon 5 h of cysteine peptidase inhibition with cell-impermeable E64. Likewise, cilia lengths and frequencies were decreased upon additional overnight treatment with the cysteine peptidase-targeting, activity-based probe DCG-04. The results suggest that cysteine cathepsin activity is required for the maintenance of the cellular protrusions not only in rodents, but also in human thyrocytes. Hence, thyrotropin stimulation was used to simulate physiological conditions that eventually lead to cathepsin-mediated thyroglobulin proteolysis, which is initiated in the thyroid follicle lumen. Immunoblotting revealed that thyrotropin stimulation conditions result in the secretion of little procathepsin L and some pro- and mature cathepsin S but no cathepsin B from the human Nthy-ori 3-1 cells. Unexpectedly, however, 24 h incubation periods with thyrotropin shortened the cilia although higher amounts of cysteine cathepsins were present in the conditioned media. These data point to the necessity of further studies to delineate which of the cysteine cathepsins plays the most prominent role in cilia shortening and/or elongation. Collectively, the results of our study provide corroboration for the hypothesis of thyroid autoregulation by local mechanisms that our group previously proposed.

Keywords:  E64; E64d; cysteine cathepsins; primary cilia; thyroid-stimulating hormone

DOI:  https://doi.org/10.3390/ijms24119292
Nefrologia (Engl Ed). 2023 Jun 14. pii: S2013-2514(23)00101-3. [Epub ahead of print]

Oral-facio-digital syndrome type I: In the differential diagnosis of autosomic dominant polycystic kidney disease, about three cases.

Unidad Multidisciplinar de Enfermedades Renales Hereditarias de la Región de Murcia (UMERH-RM)

DOI: https://doi.org/10.1016/j.nefroe.2023.06.002
EMBO J. 2023 Jun 15. e113616

A phylogenetic profiling approach identifies novel ciliogenesis genes in Drosophila and C. elegans.

Jeroen Dobbelaere, Tiffany Y Su, Balazs Erdi, Alexander Schleiffer, Alexander Dammermann.

  Cilia are cellular projections that perform sensory and motile functions in eukaryotic cells. A defining feature of cilia is that they are evolutionarily ancient, yet not universally conserved. In this study, we have used the resulting presence and absence pattern in the genomes of diverse eukaryotes to identify a set of 386 human genes associated with cilium assembly or motility. Comprehensive tissue-specific RNAi in Drosophila and mutant analysis in C. elegans revealed signature ciliary defects for 70-80% of novel genes, a percentage similar to that for known genes within the cluster. Further characterization identified different phenotypic classes, including a set of genes related to the cartwheel component Bld10/CEP135 and two highly conserved regulators of cilium biogenesis. We propose this dataset defines the core set of genes required for cilium assembly and motility across eukaryotes and presents a valuable resource for future studies of cilium biology and associated disorders.

Keywords:   Caenorhabditis elegans ; Drosophila melanogaster ; centrioles; cilia; evolution

DOI:  https://doi.org/10.15252/embj.2023113616
PLoS Genet. 2023 Jun 14. 19(6): e1010796

IFT74 variants cause skeletal ciliopathy and motile cilia defects in mice and humans.

Zeineb Bakey, Oscar A Cabrera, Julia Hoefele, Dinu Antony, Kaman Wu, Michael W Stuck, Dimitra Micha, Thibaut Eguether, Abigail O Smith, Nicole N van der Wel, Matias Wagner, Lara Strittmatter, Philip L Beales, Julie A Jonassen, Isabelle Thiffault, Maxime Cadieux-Dion, Laura Boyes, Saba Sharif, Beyhan Tüysüz, Desiree Dunstheimer, Hans W M Niessen, William Devine, Cecilia W Lo, Hannah M Mitchison, Miriam Schmidts, Gregory J Pazour.

Motile and non-motile cilia play critical roles in mammalian development and health. These organelles are composed of a 1000 or more unique proteins, but their assembly depends entirely on proteins synthesized in the cell body and transported into the cilium by intraflagellar transport (IFT). In mammals, malfunction of non-motile cilia due to IFT dysfunction results in complex developmental phenotypes that affect most organs. In contrast, disruption of motile cilia function causes subfertility, disruption of the left-right body axis, and recurrent airway infections with progressive lung damage. In this work, we characterize allele specific phenotypes resulting from IFT74 dysfunction in human and mice. We identified two families carrying a deletion encompassing IFT74 exon 2, the first coding exon, resulting in a protein lacking the first 40 amino acids and two individuals carrying biallelic splice site mutations. Homozygous exon 2 deletion cases presented a ciliary chondrodysplasia with narrow thorax and progressive growth retardation along with a mucociliary clearance disorder phenotype with severely shorted cilia. Splice site variants resulted in a lethal skeletal chondrodysplasia phenotype. In mice, removal of the first 40 amino acids likewise results in a motile cilia phenotype but with little effect on primary cilia structure. Mice carrying this allele are born alive but are growth restricted and developed hydrocephaly in the first month of life. In contrast, a strong, likely null, allele of Ift74 in mouse completely blocks ciliary assembly and causes severe heart defects and midgestational lethality. In vitro studies suggest that the first 40 amino acids of IFT74 are dispensable for binding of other IFT subunits but are important for tubulin binding. Higher demands on tubulin transport in motile cilia compared to primary cilia resulting from increased mechanical stress and repair needs could account for the motile cilia phenotype observed in human and mice.

DOI: https://doi.org/10.1371/journal.pgen.1010796
Biol Open. 2023 Jun 13. pii: bio.059976. [Epub ahead of print]

Dynein-2-driven intraciliary retrograde trafficking indirectly requires multiple interactions of IFT54 in the IFT-B complex with the dynein-2 complex.

Shunya Hiyamizu, Hantian Qiu, Yuta Tsurumi, Yuki Hamada, Yohei Katoh, Kazuhisa Nakayama.

  Within cilia, the dynein-2 complex needs to be transported as an anterograde cargo to achieve its role as a motor to drive retrograde trafficking of the intraflagellar transport (IFT) machinery containing IFT-A and IFT-B complexes. We previously showed that interactions of WDR60 and the DYNC2H1-DYNC2LI1 dimer of dynein-2 with multiple IFT-B subunits, including IFT54, are required for the trafficking of dynein-2 as an IFT cargo. However, specific deletion of the IFT54-binding site from WDR60 demonstrated only a minor effect on dynein-2 trafficking and function. We here show that the C-terminal coiled-coil region of IFT54, which participates in its interaction with the DYNC2H1-DYNC2LI1 dimer of dynein-2 and with IFT20 of the IFT-B complex, is essential for IFT-B function, and suggest that the IFT54 middle linker region between the N-terminal WDR60-binding region and the C-terminal coiled-coil is required for ciliary retrograde trafficking, probably by mediating the effective binding of IFT-B to the dynein-2 complex, and thereby ensuring dynein-2 loading onto the anterograde IFT trains. The results presented here agree with the notion predicted from the previous structural models that the dynein-2 loading onto the anterograde IFT train relies on intricate, multivalent interactions between the dynein-2 and IFT-B complexes.

Keywords:  Cilia; Dynein-2; IFT-B complex; Intraflagellar transport

DOI:  https://doi.org/10.1242/bio.059976
Nutrients. 2023 Jun 03. pii: 2621. [Epub ahead of print]15(11):

Diet and Physical Activity in Adult Dominant Polycystic Kidney Disease: A Review of the Literature.

Irene Capelli, Sarah Lerario, Valeria Aiello, Michele Provenzano, Roberta Di Costanzo, Andrea Squadrani, Anna Vella, Valentina Vicennati, Carolina Poli, Gaetano La Manna, Olga Baraldi.

  Autosomal polycystic kidney disease is the most common inherited kidney disease determining 5% of all end-stage kidney disease. The only therapy approved for this condition is Tolvaptan, which, with its aquaretic effect, has a strong effect on patients' daily life. Recently, the literature has been enriched with new works that analyze possible non-pharmacological therapeutic strategies to slow cysts' enlargement and chronic kidney disease progression. Among them, dietary schemes reducing carbohydrate intake and inducing ketoses have been demonstrated to have efficacy in several pre-clinical and clinical studies. A ketogenic diet, calorie restriction, intermittent fasting, and time-restricted feeding can reduce aerobic glycolysis and inhibit the mTOR pathway, producing a reduction in cyst cell proliferation, a reduction in kidney volume, and helping to preserve kidney function. ADPKD's burden of disease has an impact on patients' quality of life, and the possibility to play sports or carry out physical exercise can help people in everyday life. The multisystemic character of the disease, especially cardiovascular involvement, needs to be carefully evaluated to establish the quality and quantity of physical activity that patients can safely carry out.

Keywords:  ADPKD; ketogenic diet; nutrition; physical activity; polycystic kidney disease

DOI:  https://doi.org/10.3390/nu15112621
Cell Commun Signal. 2023 Jun 16. 21(1): 142

LRRC6 regulates biogenesis of motile cilia by aiding FOXJ1 translocation into the nucleus.

Dong Yun Kim, Yu Jin Sub, Hye-Youn Kim, Kyeong Jee Cho, Won Il Choi, Yo Jun Choi, Min Goo Lee, Friedhelm Hildebrandt, Heon Yung Gee.

   BACKGROUND: LRRC6 is an assembly factor for dynein arms in the cytoplasm of motile ciliated cells, and when mutated, dynein arm components remained in the cytoplasm. Here, we demonstrate the role of LRRC6 in the active nuclear translocation of FOXJ1, a master regulator for cilia-associated gene transcription.
METHODS: We generated Lrrc6 knockout (KO) mice, and we investigated the role of LRRC6 on ciliopathy development by using proteomic, transcriptomic, and immunofluorescence analysis. Experiments on mouse basal cell organoids confirmed the biological relevance of our findings.
RESULTS: The absence of LRRC6 in multi-ciliated cells hinders the assembly of ODA and IDA components of cilia; in this study, we showed that the overall expression of proteins related to cilia decreased as well. Expression of cilia-related transcripts, specifically ODA and IDA components, dynein axonemal assembly factors, radial spokes, and central apparatus was lower in Lrrc6 KO mice than in wild-type mice. We demonstrated that FOXJ1 was present in the cytoplasm and translocated into the nucleus when LRRC6 was expressed and that this process was blocked by INI-43, an importin α inhibitor.
CONCLUSIONS: Taken together, these results hinted at the LRRC6 transcriptional regulation of cilia-related genes via the nuclear translocation of FOXJ1. Video Abstract.

Keywords:  FOXJ1; LRRC6; Motile cilia; Nuclear translocation; Primary ciliary dyskinesia

DOI:  https://doi.org/10.1186/s12964-023-01135-y
Sci Rep. 2023 Jun 09. 13(1): 9410

The Caenorhabditis elegans Shugoshin regulates TAC-1 in cilia.

R Reed, K Park, B Waddell, T A Timbers, C Li, K Baxi, R M Giacomin, M R Leroux, C E Carvalho.

The conserved Shugoshin (SGO) protein family is essential for mediating proper chromosome segregation from yeast to humans but has also been implicated in diverse roles outside of the nucleus. SGO's roles include inhibiting incorrect spindle attachment in the kinetochore, regulating the spindle assembly checkpoint (SAC), and ensuring centriole cohesion in the centrosome, all functions that involve different microtubule scaffolding structures in the cell. In Caenorhabditis elegans, a species with holocentric chromosomes, SGO-1 is not required for cohesin protection or spindle attachment but appears important for licensing meiotic recombination. Here we provide the first functional evidence that in C. elegans, Shugoshin functions in another extranuclear, microtubule-based structure, the primary cilium. We identify the centrosomal and microtubule-regulating transforming acidic coiled-coil protein, TACC/TAC-1, which also localizes to the basal body, as an SGO-1 binding protein. Genetic analyses indicate that TAC-1 activity must be maintained below a threshold at the ciliary base for correct cilia function, and that SGO-1 likely participates in constraining TAC-1 to the basal body by influencing the function of the transition zone 'ciliary gate'. This research expands our understanding of cellular functions of Shugoshin proteins and contributes to the growing examples of overlap between kinetochore, centrosome and cilia proteomes.

DOI: https://doi.org/10.1038/s41598-023-36430-8
Proc Natl Acad Sci U S A. 2023 Jun 20. 120(25): e2218951120

Robust acoustic trapping and perturbation of single-cell microswimmers illuminate three-dimensional swimming and ciliary coordination.

Mingyang Cui, Susan K Dutcher, Philip V Bayly, J Mark Meacham.

  We report a label-free acoustic microfluidic method to confine single, cilia-driven swimming cells in space without limiting their rotational degrees of freedom. Our platform integrates a surface acoustic wave (SAW) actuator and bulk acoustic wave (BAW) trapping array to enable multiplexed analysis with high spatial resolution and trapping forces that are strong enough to hold individual microswimmers. The hybrid BAW/SAW acoustic tweezers employ high-efficiency mode conversion to achieve submicron image resolution while compensating for parasitic system losses to immersion oil in contact with the microfluidic chip. We use the platform to quantify cilia and cell body motion for wildtype biciliate cells, investigating effects of environmental variables like temperature and viscosity on ciliary beating, synchronization, and three-dimensional helical swimming. We confirm and expand upon the existing understanding of these phenomena, for example determining that increasing viscosity promotes asynchronous beating. Motile cilia are subcellular organelles that propel microorganisms or direct fluid and particulate flow. Thus, cilia are critical to cell survival and human health. The unicellular alga Chlamydomonas reinhardtii is widely used to investigate the mechanisms underlying ciliary beating and coordination. However, freely swimming cells are difficult to image with sufficient resolution to capture cilia motion, necessitating that the cell body be held during experiments. Acoustic confinement is a compelling alternative to use of a micropipette, or to magnetic, electrical, and optical trapping that may modify the cells and affect their behavior. Beyond establishing our approach to studying microswimmers, we demonstrate a unique ability to mechanically perturb cells via rapid acoustic positioning.

Keywords:  acoustic tweezers; acoustofluidics; cilia and flagella; microswimmers

DOI:  https://doi.org/10.1073/pnas.2218951120
Cells. 2023 May 24. pii: 1467. [Epub ahead of print]12(11):

Primary Ciliary Dyskinesia Patient-Specific hiPSC-Derived Airway Epithelium in Air-Liquid Interface Culture Recapitulates Disease Specific Phenotypes In Vitro.

Laura von Schledorn, David Puertollano Martín, Nicole Cleve, Janina Zöllner, Doris Roth, Ben Ole Staar, Jan Hegermann, Felix C Ringshausen, Janna Nawroth, Ulrich Martin, Ruth Olmer.

  Primary ciliary dyskinesia (PCD) is a rare heterogenic genetic disorder associated with perturbed biogenesis or function of motile cilia. Motile cilia dysfunction results in diminished mucociliary clearance (MCC) of pathogens in the respiratory tract and chronic airway inflammation and infections successively causing progressive lung damage. Current approaches to treat PCD are symptomatic, only, indicating an urgent need for curative therapeutic options. Here, we developed an in vitro model for PCD based on human induced pluripotent stem cell (hiPSC)-derived airway epithelium in Air-Liquid-Interface cultures. Applying transmission electron microscopy, immunofluorescence staining, ciliary beat frequency, and mucociliary transport measurements, we could demonstrate that ciliated respiratory epithelia cells derived from two PCD patient-specific hiPSC lines carrying mutations in DNAH5 and NME5, respectively, recapitulate the respective diseased phenotype on a molecular, structural and functional level.

Keywords:  PCD; air-liquid interface culture; human induced pluripotent stem cells

DOI:  https://doi.org/10.3390/cells12111467