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Proceedings of the National Academy of... Sep 2021Skeletal ciliopathies (e.g., Jeune syndrome, short rib polydactyly syndrome, and Sensenbrenner syndrome) are frequently associated with nephronophthisis-like cystic...
Skeletal ciliopathies (e.g., Jeune syndrome, short rib polydactyly syndrome, and Sensenbrenner syndrome) are frequently associated with nephronophthisis-like cystic kidney disease and other organ manifestations. Despite recent progress in genetic mapping of causative loci, a common molecular mechanism of cartilage defects and cystic kidneys has remained elusive. Targeting two ciliary chondrodysplasia loci ( and ) by CRISPR/Cas9 mutagenesis, we established models for skeletal ciliopathies in Froglets exhibited severe limb deformities, polydactyly, and cystic kidneys, closely matching the phenotype of affected patients. A data mining-based in silico screen found to be related to known skeletal ciliopathy genes. CRISPR/Cas9 targeting replicated limb malformations and renal cysts identical to the models of established disease genes. Loss of Ttc30a impaired embryonic renal excretion and ciliogenesis because of altered posttranslational tubulin acetylation, glycylation, and defective axoneme compartmentalization. transcripts are enriched in chondrocytes and osteocytes of single-cell RNA-sequenced embryonic mouse limbs. We identify TTC30A/B as an essential node in the network of ciliary chondrodysplasia and nephronophthisis-like disease proteins and suggest that tubulin modifications and cilia segmentation contribute to skeletal and renal ciliopathy manifestations of ciliopathies in a cell type-specific manner. These findings have implications for potential therapeutic strategies.
Topics: Animals; Bone and Bones; Ciliopathies; Craniosynostoses; Cytoskeletal Proteins; Disease Models, Animal; Ectodermal Dysplasia; Embryo, Nonmammalian; Musculoskeletal Abnormalities; Phenotype; Polycystic Kidney Diseases; Tubulin; Xenopus laevis
PubMed: 34548398
DOI: 10.1073/pnas.2106770118 -
Molecular Vision 2021Cytoplasmic dyneins (dynein-1 and dynein-2) transport cargo toward the minus end of microtubules and thus, are termed the "retrograde" cellular motor. Dynein-1 cargo may... (Review)
Review
Cytoplasmic dyneins (dynein-1 and dynein-2) transport cargo toward the minus end of microtubules and thus, are termed the "retrograde" cellular motor. Dynein-1 cargo may include nuclei, mitochondria, membrane vesicles, lysosomes, phagosomes, and other organelles. For example, dynein-1 works in the cell body of eukaryotes to move cargo toward the microtubule minus end and positions the Golgi complex. Dynein-1 also participates in the movement of chromosomes and the positioning of mitotic spindles during cell division. In contrast, dynein-2 is present almost exclusively within cilia where it participates in retrograde intraflagellar transport (IFT) along the axoneme to return kinesin-2 subunits, BBSome, and IFT particles to the cell body. Cytoplasmic dyneins are hefty 1.5 MDa complexes comprised of dimers of heavy, intermediate, light intermediate, and light chains. Missense mutations of human are associated with malformations of cortical development (MCD) or spinal muscular atrophy with lower extremity predominance (SMA-LED). Missense mutations in are causative of short-rib polydactyly syndrome type III and nonsyndromic retinitis pigmentosa. We review mutations of the two dynein heavy chains and their effect on postnatal retina development and discuss consequences of deletion of in the mouse retina.
Topics: Animals; Cytoplasmic Dyneins; Gene Expression; Humans; Mice; Mutation; Photoreceptor Cells, Vertebrate; Retinal Diseases
PubMed: 34526758
DOI: No ID Found -
Protein Science : a Publication of the... Nov 2021Phosphatidylserine (PS) synthase 1 (PSS1) of mammalian cells is a multiple membrane-spanning protein of the endoplasmic reticulum (ER) and regulated by inhibition with...
Phosphatidylserine (PS) synthase 1 (PSS1) of mammalian cells is a multiple membrane-spanning protein of the endoplasmic reticulum (ER) and regulated by inhibition with the product PS. Alanine-scanning mutagenesis of PSS1 has revealed eight amino acid residues as those crucial for its activity and six as those important for its regulation. Furthermore, three missense mutations in the human PSS1 gene, which lead to regulatory dysfunctions of PSS1 and are causative of Lenz-Majewski syndrome, have been identified. In this study, we investigated the membrane topology of PSS1 by means of epitope insertion and immunofluorescence. According to a 10-transmembrane segment model supported by topology analysis of PSS1, all the 8 amino acid residues crucial for the enzyme activity were localized to the luminal side of the lipid bilayer or the lumen of the ER, whereas all the 9 amino acid residues involved in the enzyme regulation were localized to the cytosol or the cytoplasmic side of the lipid bilayer of the ER. This localization of the functional amino acid residues suggests that PSS1 is regulated by inhibition with PS in the cytoplasmic leaflet of the ER membrane and synthesizes PS at the luminal leaflet.
Topics: Endoplasmic Reticulum; HeLa Cells; Humans; Intracellular Membranes; Lipid Bilayers; Nitrogenous Group Transferases
PubMed: 34516042
DOI: 10.1002/pro.4182 -
Cells Jul 2021Although ubiquitously present, the relevance of cilia for vertebrate development and health has long been underrated. However, the aberration or dysfunction of ciliary... (Review)
Review
Although ubiquitously present, the relevance of cilia for vertebrate development and health has long been underrated. However, the aberration or dysfunction of ciliary structures or components results in a large heterogeneous group of disorders in mammals, termed ciliopathies. The majority of human ciliopathy cases are caused by malfunction of the ciliary dynein motor activity, powering retrograde intraflagellar transport (enabled by the cytoplasmic dynein-2 complex) or axonemal movement (axonemal dynein complexes). Despite a partially shared evolutionary developmental path and shared ciliary localization, the cytoplasmic dynein-2 and axonemal dynein functions are markedly different: while cytoplasmic dynein-2 complex dysfunction results in an ultra-rare syndromal skeleto-renal phenotype with a high lethality, axonemal dynein dysfunction is associated with a motile cilia dysfunction disorder, primary ciliary dyskinesia (PCD) or Kartagener syndrome, causing recurrent airway infection, degenerative lung disease, laterality defects, and infertility. In this review, we provide an overview of ciliary dynein complex compositions, their functions, clinical disease hallmarks of ciliary dynein disorders, presumed underlying pathomechanisms, and novel developments in the field.
Topics: Animals; Axonemal Dyneins; Cilia; Ciliopathies; Cytoplasmic Dyneins; Humans; Kartagener Syndrome; Polymorphism, Genetic; Short Rib-Polydactyly Syndrome
PubMed: 34440654
DOI: 10.3390/cells10081885 -
Journal of Applied Research in... Jul 2021People with Down syndrome (DS) have a unique medical profile which may impact views of health. We aimed to explore the use of global health measures in DS.
PURPOSE
People with Down syndrome (DS) have a unique medical profile which may impact views of health. We aimed to explore the use of global health measures in DS.
METHODS
Prospective survey in the Mass General Hospital Down Syndrome Program (MGH DSP) from December 2018 to July 2019 with Patient Reported Outcomes Measurement Information System (PROMIS)® instruments of global health. Analyses included use of scoring manuals, descriptive statistics and dependent samples t test.
RESULTS
Seventeen adolescents, 48 adults with DS and 88 caregivers returned surveys; 137 were complete. Incomplete responses and notes showed limitations of the instruments in this population. Global health T-scores did not differ from the available comparative standardized scores to these measures from PROMIS® reference population (p > 0.05).
CONCLUSIONS
In the MGH DSP, pilot global health instruments were completed by some adults with DS and caregivers, with some limitations and scores similar to the PROMIS® reference population.
Topics: Adolescent; Adult; Down Syndrome; Global Health; Humans; Intellectual Disability; Prospective Studies; Quality of Life; Surveys and Questionnaires
PubMed: 33759305
DOI: 10.1111/jar.12866 -
Cell Death & Disease Jan 2021Mutations of WD40 repeat domain 60 (WDR60) have been identified in short-rib polydactyly syndromes (SRPS I-V), a group of lethal congenital disorders characterized by...
Mutations of WD40 repeat domain 60 (WDR60) have been identified in short-rib polydactyly syndromes (SRPS I-V), a group of lethal congenital disorders characterized by short ribs, polydactyly, and a range of extraskeletal phenotypes. However, the underlying mechanism is still unclear. Here, we report that WDR60 is essential for embryonic development and plays a critical role in the multipolar-bipolar transition and migration of newborn neurons during brain development. Mechanically, we found that WDR60 was located at the microtubule-organizing center to control microtubule organization and possibly, the trafficking of cellular components. Importantly, the migration defect caused by Wdr60 knockdown could be rescued by the stable form of α-Tubulin, α-Tubulin (an acetylation-mimicking mutant). These findings identified a non-cilia function of WDR60 and provided insight into its biological function, as well as the pathogenesis of WDR60 deficiency associated with SRPS.
Topics: Adaptor Proteins, Signal Transducing; Animals; Cell Movement; Female; Humans; Mice; Neurogenesis; Neurons; Rats; Short Rib-Polydactyly Syndrome
PubMed: 33436552
DOI: 10.1038/s41419-020-03363-3 -
Genetics in Medicine : Official Journal... Jan 2021
PubMed: 33169000
DOI: 10.1038/s41436-020-01033-5 -
Cureus Sep 2020Microcephalic osteodysplastic primordial dwarfism type 2 (MOPD2) is a rare autosomal recessive disorder that presents as a myriad of skeletal abnormalities collectively...
Microcephalic osteodysplastic primordial dwarfism type 2 (MOPD2) is a rare autosomal recessive disorder that presents as a myriad of skeletal abnormalities collectively termed as osteodysplasia, which have their onset during intrauterine life with the fetus exhibiting intrauterine growth restriction. Affected individuals also tend to have a very small head size that is more than three standard deviations (SD) below the mean for a population termed microcephalic. The growth problems progress postnatally, causing stunted growth or short stature. In this report, we present the case of two siblings: a 15-year-old unvaccinated female weighing 8 kg (case one), and a seven-year-old unvaccinated female weighing 6 kg (case two), who presented to the Department of Pediatrics, Unit 2 at the Civil Hospital in Karachi, Pakistan, complaining of short stature since birth.
PubMed: 33042696
DOI: 10.7759/cureus.10258 -
Journal of Postgraduate Medicine 2020
Topics: Adaptor Proteins, Signal Transducing; Cytoskeletal Proteins; Dyspnea; Fever; Growth Plate; Humans; Infant; Male; Radiography; Ribs; Short Rib-Polydactyly Syndrome; Sweating
PubMed: 33037165
DOI: 10.4103/jpgm.JPGM_4_20 -
Molecular Genetics & Genomic Medicine Dec 2020Skeletal ciliopathies are a group of clinically and genetically heterogeneous disorders with the spectrum of severity spanning from relatively mild to prenatally lethal....
BACKGROUND
Skeletal ciliopathies are a group of clinically and genetically heterogeneous disorders with the spectrum of severity spanning from relatively mild to prenatally lethal. The aim of our study was to identify pathogenic mutations in a Chinese family with two siblings presenting a Short-rib polydactyly syndrome (SRPS)-like phenotype.
METHOD
Karyotyping and NGS-based CNVseq were performed. Obtaining the negative results in karyotyping and CNVseq, whole-exome sequencing (WES) using genomic DNA (gDNA) extracted from the umbilical cord blood of the first fetus was carried out, followed by bioinformation analysis. The candidate pathogenic variants were confirmed by Sanger sequencing in the family.
RESULTS
No chromosomal abnormalities and pathogenic copy number variations (CNVs) were detected in the affected fetus with SRPS-like phenotype. WES analysis identified two novel compound heterozygous variants in DYNC2LI1, c.358G>T (p.Pro120Ser; NM_001193464), and c.928A>T (p.Lys310Ter; NM_ 001193464). Bioinformatics analysis suggested that c.358G>T (p.Pro120Ser) was likely pathogenic and c.928A>T (p.Lys310Ter) was pathogenic. Sanger sequencing of the two variants in family reveal that c.358G>T was from paternal origin and c.928A>T was from maternal origin, and the second affected fetus had the same compound heterozygous variants in DYNC2LI1. Definitive diagnosis of short-rib thoracic dysplasia 15 with polydactyly (SRTD15) was made in the family.
CONCLUSION
Our results expand the mutational spectrum of DYNC2LI1 in severe skeletal ciliopathies. WES facilitates the accurate prenatal diagnosis of fetal skeletal ciliopathy, and provides helpful information for genetic counseling.
Topics: Adult; Ciliopathies; Cytoplasmic Dyneins; Female; Fetus; Heterozygote; Humans; Male; Point Mutation; Pregnancy; Short Rib-Polydactyly Syndrome; Ultrasonography, Prenatal; Whole Genome Sequencing
PubMed: 33030252
DOI: 10.1002/mgg3.1524