scholarly journals Decoding G0 somatic mutants through deep phenotyping and mosaic pattern analysis in the zebrafish skeleton

2018 ◽  
Author(s):  
Claire J. Watson ◽  
Adrian T. Monstad-Rios ◽  
Rehaan M. Bhimani ◽  
Charlotte Gistelinck ◽  
Andy Willaert ◽  
...  
Keyword(s):  
Pattern Analysis ◽  
Bone Diseases ◽  
Loss Of Function ◽  
Biological Factors ◽  
Mosaic Pattern ◽  
Skeletal Disease ◽  
Genetic Mosaicism ◽  
Clonal Fragmentation ◽  
Somatic Mutant ◽  
Deep Phenotyping

ABSTRACTGenetic mosaicism manifests as spatially variable phenotypes, whose detection and interpretation remains challenging. This study identifies biological factors influencing spatial phenotypic patterns in the skeletons of somatic mutant zebrafish, and tests methods for their analysis using deep phenotyping. We explore characteristics of loss-of-function clusters in the skeleton of CRISPR-edited G0 ("crispant") zebrafish, and identify a distinctive size distribution shown to arise from clonal fragmentation and merger events. Using microCT-based phenomics, we describe diverse phenotypic manifestations in somatic mutants for genes implicated in monogenic (plod2 and bmp1a) and polygenic (wnt16) bone diseases, each showing convergence with germline mutant phenomes. Finally, we describe statistical frameworks for phenomic analysis which confers heightened sensitivity in discriminating somatic mutant populations, and quantifies spatial phenotypic variation. Our studies provide strategies for decoding spatially variable phenotypes which, paired with CRISPR-based screens, can identify genes contributing to skeletal disease.

Mathematical modeling of cement paste microstructure by mosaic pattern. Part II. Application

1997 ◽  
Vol 12 (7) ◽  
pp. 1741-1746 ◽  
Author(s):  
Paul D. Tennis ◽  
Yunping Xi ◽  
Hamlin M. Jennings
Keyword(s):  
Mathematical Modeling ◽  
Spatial Distribution ◽  
Portland Cement ◽  
Cement Paste ◽  
Pattern Analysis ◽  
Mosaic Pattern ◽  
Cement Pastes ◽  
Multiphase Materials ◽  
Spatial Features ◽  
Complex Shapes

A model based on mosaic pattern analysis is shown to have the potential to describe the complex shapes and spatial distribution of phases in the microstructures of multiphase materials. Several characteristics of both micrographs of portland cement pastes and images generated using the few parameters of the model are determined and, for the most part, agreement is good. The advantage is that spatial features of the microstructures can be captured by a few parameters.

scholarly journals Natural human knockouts and Mendelian disorders: deep phenotyping in Italian isolates

2021 ◽  
Author(s):  
Beatrice Spedicati ◽  
Massimiliano Cocca ◽  
Roberto Palmisano ◽  
Flavio Faletra ◽  
Caterina Barbieri ◽  
...  
Keyword(s):  
Signs And Symptoms ◽  
Loss Of Function ◽  
Delayed Treatment ◽  
Mendelian Disorders ◽  
Naturally Occurring ◽  
Function Loss ◽  
Genetic Isolates ◽  
Autosomal Recessive Diseases ◽  
Deep Phenotyping

AbstractWhole genome sequencing (WGS) allows the identification of human knockouts (HKOs), individuals in whom loss of function (LoF) variants disrupt both alleles of a given gene. HKOs are a valuable model for understanding the consequences of genes function loss. Naturally occurring biallelic LoF variants tend to be significantly enriched in “genetic isolates,” making these populations specifically suited for HKO studies. In this work, a meticulous WGS data analysis combined with an in-depth phenotypic assessment of 947 individuals from three Italian genetic isolates led to the identification of ten biallelic LoF variants in ten OMIM genes associated with known autosomal recessive diseases. Notably, only a minority of the identified HKOs (C7, F12, and GPR68 genes) displayed the expected phenotype. For most of the genes, instead, (ACADSB, FANCL, GRK1, LGI4, MPO, PGAM2, and RP1L1), the carriers showed none or few of the signs and symptoms typically associated with the related diseases. Of particular interest is a case presenting with a FANCL biallelic LoF variant and a positive diepoxybutane test but lacking a full Fanconi anemia phenotypic spectrum. Identifying KO subjects displaying expected phenotypes suggests that the lack of correct genetic diagnoses may lead to inappropriate and delayed treatment. In contrast, the presence of HKOs with phenotypes deviating from the expected patterns underlines how LoF variants may be responsible for broader phenotypic spectra. Overall, these results highlight the importance of in-depth phenotypical characterization to understand the role of LoF variants and the advantage of studying these variants in genetic isolates.

Control of osteocyte dendrite formation by Sp7 and its target gene osteocrin

2021 ◽  
Author(s):  
Jialiang S Wang ◽  
Tushar Kamath ◽  
Fatemeh Mirzamohammadi ◽  
Daniel Rotter ◽  
Hironori Hojo ◽  
...  
Keyword(s):  
Gene Networks ◽  
Target Gene ◽  
Target Genes ◽  
Bone Matrix ◽  
Bone Diseases ◽  
Dendrite Formation ◽  
Skeletal Disease ◽  
Mineralized Bone Matrix

Osteocytes use an elaborate network of dendritic connections to control bone remodeling. Some osteoblasts embed within mineralized bone matrix, change shape, and become osteocytes. The molecular circuitry that drives dendrite formation during "osteocytogenesis" is poorly understood. Here we show that deletion of Sp7, a gene linked to rare and common skeletal disease, in mature osteoblasts and osteocytes causes severe defects in osteocyte dendrites. Unbiased profiling of Sp7 target genes and binding sites reveals unexpected repurposing of this transcription factor to drive dendrite formation. Osteocrin is a Sp7 target gene that promotes osteocyte dendrite formation and rescues phenotypic and molecular defects in Sp7-deficient mice. Single-cell RNA-sequencing demonstrates overt defects in osteocyte maturation in vivo in the absence of Sp7. Sp7-dependent gene networks enriched in developing osteocytes are associated with rare and common human skeletal traits. Moreover, humans homozygous for the osteogenesis imperfecta-causing SP7R316C mutation show dramatic defects in osteocyte morphology. Genes that mark osteocytes in vivo and that are regulated by Sp7 in vitro are highly enriched in neurons, highlighting shared features between osteocytic and neuronal connectivity. Taken together, these findings reveal a crucial role for Sp7 and its target gene Osteocrin in osteocytogenesis, demonstrating that pathways that control osteocyte development influence human bone diseases.

scholarly journals Genome Wide Association Metanalysis Of Skull Bone Mineral Density Identifies Loci Relevant For Osteoporosis And Craniosynostosis

2021 ◽  
Author(s):  
Carolina Medina-Gomez ◽  
Benjamin H. Mullin ◽  
Alessandra Chesi ◽  
Vid Prijatelj ◽  
John P. Kemp ◽  
...  
Keyword(s):  
Bone Mineral Density ◽  
Bone Mineral ◽  
Bone Growth ◽  
Bone Diseases ◽  
Cranial Bone ◽  
Skull Bone ◽  
Loss Of Function ◽  
Bone Biology ◽  
Mineral Density ◽  
Genome Wide

Skull bone mineral density (SK-BMD) provides a suitable trait for the discovery of genes important to bone biology in general, and particularly for identifying components unique to intramembranous ossification, which cannot be captured at other skeletal sites. We assessed genetic determinants of SK-BMD in 43,800 individuals, identifying 59 genome-wide significant loci (4 novel), explaining 12.5% of its variance. Pathway and enrichment analyses of the association signals resulted in clustering within gene-sets involved in regulating the development of the skeleton; overexpressed in the musculoskeletal system; and enriched in enhancer and transcribed regions in osteoblasts. From the four novel loci (mapping to ZIC1, PRKAR1A, ATP6V1C1, GLRX3), two (ZIC1 and PRKAR1A) have previously been related to craniofacial developmental defects. Functional validation of skull development in zebrafish revealed abnormal cranial bone initiation that culminated in ectopic sutures and reduced BMD in mutated zic1 and atp6v1c1 fish and asymmetric bone growth and elevated BMD in mutated prkar1a fish. We confirmed a role of ZIC1 loss-of-function in suture patterning and discovered ATP6V1C1 gene associated with suture development. In light of the evidence presented suggesting that SK-BMD is genetically related to craniofacial abnormalities, our study opens new avenues to the understanding of the pathophysiology of craniofacial defects and towards the effective pharmacological treatment of bone diseases.

Metabolic bone diseases

2018 ◽  
pp. 483-524
Author(s):  
Gavin Clunie ◽  
Nick Wilkinson ◽  
Elena Nikiphorou ◽  
Deepak R. Jadon
Keyword(s):  
Risk Assessment ◽  
Vitamin D ◽  
Bone Diseases ◽  
Sapho Syndrome ◽  
Extensive Review ◽  
Metabolic Bone Diseases ◽  
Skeletal Disease ◽  
Metabolic Bone ◽  
Bone Dysplasias ◽  
Parathyroid Disease

The Oxford Handbook of Rheumatology, 4th edition, includes a chapter on metabolic bone diseases with an extensive review of the modern management of all forms of osteoporosis and fracture risk assessment including glucocorticoid-induced osteoporosis, idiopathic juvenile osteoporosis, and DXA scanning. The chapter outlines the salient features of other less common and occasionally encountered bone diseases found in rheumatological practice including vitamin D deficiency, osteomalacia and rickets, hypercalcaemia, parathyroid disease, Paget’s disease of bone, SAPHO syndrome, osteochondroses, osteonecrosis, fibrous dysplasia, sclerosing bone dysplasias, and bone tumours. New to this Handbook edition is a section on the main childhood autoinflammatory conditions manifest as skeletal disease under the umbrella term chronic non-bacterial osteomyelitis.

scholarly journals WISP3, the Gene Responsible for the Human Skeletal Disease Progressive Pseudorheumatoid Dysplasia, Is Not Essential for Skeletal Function in Mice

2005 ◽  
Vol 25 (1) ◽  
pp. 414-421 ◽  
Author(s):  
Wendy E. Kutz ◽  
Yaoqin Gong ◽  
Matthew L. Warman
Keyword(s):  
Neural Development ◽  
Autosomal Recessive ◽  
Mendelian Inheritance ◽  
Tissue Growth ◽  
Skeletal Growth ◽  
Loss Of Function ◽  
Progressive Pseudorheumatoid Dysplasia ◽  
Skeletal Disease ◽  
Cysteine Rich Protein

ABSTRACT In humans, loss-of-function mutations in WISP3 cause the autosomal recessive skeletal disease progressive pseudorheumatoid dysplasia (PPD) (Online Mendelian Inheritance in Man database number 208230). WISP3 encodes Wnt1-inducible signaling protein 3, a cysteine-rich, multidomain, secreted protein, whose paralogous CCN (connective tissue growth factor/cysteine-rich protein 61/nephroblastoma overexpressed) family members have been implicated in diverse biologic processes including skeletal, vascular, and neural development. To understand the role of WISP3 in the skeleton, we targeted the Wisp3 gene in mice by creating a mutant allele comparable to that which causes human disease. We also created transgenic mice that overexpress human WISP3 in cartilage. Surprisingly, homozygous Wisp3 mutant mice appear normal and do not recapitulate any of the morphological, radiographic, or histological abnormalities seen in patients with PPD. Mice that overexpress WISP3 are also normal. We conclude, that in contrast to humans, Wisp3 is not an essential participant during skeletal growth or homeostasis in mice.

scholarly journals Replacing the PDZ-interacting C-termini of DSCAM and DSCAML1 with epitope tags causes different phenotypic severity in different cell populations

eLife ◽  
2016 ◽  
Vol 5 ◽  
Author(s):  
Andrew M Garrett ◽  
Abigail LD Tadenev ◽  
Yuna T Hammond ◽  
Peter G Fuerst ◽  
Robert W Burgess
Keyword(s):  
Network Formation ◽  
Pdz Domain ◽  
Cell Types ◽  
Scaffolding Proteins ◽  
Loss Of Function ◽  
Mosaic Pattern ◽  
C Terminus ◽  
Different Types ◽  
Developmental Cell Death ◽  
Different Cell Types

Different types of neurons in the retina are organized vertically into layers and horizontally in a mosaic pattern that helps ensure proper neural network formation and information processing throughout the visual field. The vertebrate Dscams (DSCAM and DSCAML1) are cell adhesion molecules that support the development of this organization by promoting self-avoidance at the level of cell types, promoting normal developmental cell death, and directing vertical neurite stratification. To understand the molecular interactions required for these activities, we tested the functional significance of the interaction between the C-terminus of the Dscams and multi-PDZ domain-containing scaffolding proteins in mouse. We hypothesized that this PDZ-interacting domain would mediate a subset of the Dscams’ functions. Instead, we found that in the absence of these interactions, some cell types developed almost normally, while others resembled complete loss of function. Thus, we show differential dependence on this domain for Dscams’ functions in different cell types.

Response of Osteoporotic Bone to the Implantation of Biphasic Calcium Phosphate (BCP) Bioceramics

2018 ◽  
Vol 780 ◽  
pp. 20-24
Author(s):  
Aleksandrs Grisulonoks ◽  
Ilze Salma ◽  
Girts Salms ◽  
Laura Neimane ◽  
Andrejs Skagers ◽  
...  
Keyword(s):  
Bone Mineral Density ◽  
Calcium Phosphate ◽  
Biphasic Calcium Phosphate ◽  
Bone Fragility ◽  
Bone Diseases ◽  
Osteoporotic Bone ◽  
Mineral Density ◽  
Skeletal Disease ◽  
Mineral Structure ◽  
Pathologic Processes

Osteoporosis is a chronic, metabolic and systemic skeletal disease characterized by low bone mineral density (BMD) and micro-architectural deterioration, resulting in increased bone fragility and fracture risk. Changes in the mineral structure occur due to aging or because of progressive pathologic processes such as osteoporosis, as well as in both aging and effects of bone diseases.

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