Search bioRxiv⌕ Search

Biology subjects

Mizuno, S.

Publications and source records attributed to Mizuno, S..

43 records · Page 3Linked to original sources

Cables2 Is a novel Smad2-regulatory factor essential for early embryonic development in mice

CDK5 and Abl enzyme substrate 2 (Cables2), a member of the Cables family that has a C-terminal cyclin box-like domain, is widely expressed in adult mouse tissues. However, the physiological role of Cables2 in vivo is unknown. We show here that Cables2-deficiency causes post-gastrulation embryonic lethality in mice. The mutant embryos progress to gastrulation, but then arrest, and fail to grow. Analysis of gene expression patterns reveals that formation of the anterior visceral endoderm and the primitive streak is impaired in Cables2-deficient embryos. Tetraploid complementation analyses support the critical requirement of Cables2 in both the epiblast and visceral endoderm for progression of embryogenesis. In addition, we show that Cables2 physically interacts with a key mediator of the canonical Nodal pathway, Smad2, and augments its transcriptional activity. These findings provide novel insights into the essential role of Cables2 in the early embryonic development in mice.

developmental biology↗

Clustering by phenotype and genome-wide association study in autism

BackgroundAutism spectrum disorder (ASD) has phenotypically and genetically heterogeneous characteristics. A simulation study demonstrated that attempts to categorize patients with a complex disease into more homogeneous subgroups could have more power to elucidate hidden heritability. MethodsWe conducted cluster analyses using the k-means algorithm with a cluster number of 15 based on phenotypic variables from the Simons Simplex Collection (SSC). As a preliminary study, we conducted a conventional genome-wide association study (GWAS) with a dataset of 597 ASD cases and 370 controls. In the second step, we divided cases based on the clustering results and conducted GWAS in each of the subgroups vs controls (cluster-based GWAS). We also conducted cluster-based GWAS on another SSC dataset of 712 probands and 354 controls in the replication stage. ResultsIn the preliminary study, we observed no significant associations. In the second step of cluster-based GWASs, we identified 65 chromosomal loci, which included 30 intragenic loci located in 21 genes and 35 intergenic loci that satisfied the threshold of P<5.0x10-8. Some of these loci were located within or near previously reported candidate genes for ASD: CDH5, CNTN5, CNTNAP5, DNAH17, DPP10, DSCAM, FOXK1, GABBR2, GRIN2A5, ITPR1, NTM, SDK1, SNCA and SRRM4. Of these 65 significant chromosomal loci, rs11064685 located within the SRRM4 gene had a significantly different distribution in the cases vs. controls in the replication cohort. ConclusionsThese findings suggest that clustering may successfully identify subgroups with relatively homogeneous disease etiologies. Further cluster validation and replication studies are warranted in larger cohorts.

neuroscience↗

Management of family relationship informationfor a three-generation cohort study

A system for inputting and storing family information, named \"BirThree Enrollment,\" was developed to promote a birth and three-generation cohort study (BirThree Cohort Study), and this system was operated successfully. In the study, it was necessary to satisfy many operational demands. Input information is overwritten and changed continuously. Complex kinship information must be quickly and accurately input and corrected, and information on those families not yet recruited must be retrieved. For these purposes, many devices are needed, from an input interface to the internal data structure. In the field of genetic statistics, a simple standard expressive form is used for describing family structure. This form has sufficient information for genetics; however, we developed this form further for our purposes in conducting the BirThree Cohort Study. To provide information about family roles as required in the BirThree Cohort Study, we expanded the data structure, and constructed the system that is able to be used for the daily operation. In our system, family pedigree information is stored along with initial clinical information, and enabled the input of all self-reported information to the data base. Operators are able to input this family information before the day is out. As a result, when recruitment is completed, family information will be completed concurrently. Therefore, it is possible to immediately know a certain persons family structure. By using our system, data correction was improved dramatically, and the system was operated successfully. This study is the first report of the method for storing three generations of family data.

epidemiology↗

Identification of SMARCD1 as a syndromic intellectual disability gene that is required for memory and context-dependent regulation of neuronal genes in Drosophila

Mutations in several genes encoding components of the SWI/SNF chromatin remodeling complex cause syndromic intellectual disability (ID). Here, we report on 5 individuals with mutations in the SMARCD1 gene, presenting with ID, developmental delay, hypotonia, feeding difficulties, and small extremities. The mutations were proven to be de novo in 4 of the 5 individuals. Mutations in other SWI/SNF components cause Coffin-Siris, Nicolaides-Baraitser, or other syndromic ID disorders. Although the individuals presented here have some clinical overlap with these disorders, they lack the typical facial dysmorphisms. To gain insight into the function of SMARCD1 in neurons, we investigated the Drosophila ortholog, Bap60, in postmitotic memory-forming neurons of the adult Drosophila mushroom body (MB). Targeted knockdown of Bap60 in the MB of adult flies causes defects in long-term memory. Mushroom body specific transcriptome analysis revealed that Bap60 is required for context-dependent expression of genes involved in neuron function and development in juvenile flies when synaptic connections are actively being formed in response to experience. Taken together, we identify SMARCD1 mutations as a novel cause of ID, and establish a role for the SMARCD1 ortholog Bap60 in regulation of neurodevelopmental genes during a critical time window of juvenile adult brain development that is essential in establishing neuronal circuits that are required for learning and memory.

genetics↗

ALPHLARD: a Bayesian method for analyzing HLA genes from whole genome sequence data

Although human leukocyte antigen (HLA) genotyping based on amplicon, whole exome sequence (WES), and RNA sequence data has been achieved in recent years, accurate genotyping from whole genome sequence (WGS) data remains a challenge due to the low depth. Furthermore, there is no method to identify the sequences of unknown HLA types not registered in HLA databases. We developed a Bayesian model, called ALPHLARD, that collects reads potentially generated from HLA genes and accurately determines a pair of HLA types for each of HLA-A, -B, -C, -DPA1, -DPB1, -DQA1, -DQB1, and -DRB1 genes at 6-digit resolution. Furthermore, ALPHLARD can detect rare germline variants not stored in HLA databases and call somatic mutations from paired normal and tumor sequence data. We illustrate the capability of ALPHLARD using 253 WES data and 25 WGS data from Illumina platforms. By comparing the results of HLA genotyping from SBT and amplicon sequencing methods, ALPHLARD achieved 98.8% for WES data and 98.5% for WGS data at 4-digit resolution. We also detected three somatic point mutations and one case of loss of heterozygosity in the HLA genes from the WGS data. ALPHLARD showed good performance for HLA genotyping even from low-coverage data. It also has a potential to detect rare germline variants and somatic mutations in HLA genes. It would help to fill in the current gaps in HLA reference databases and unveil the immunological significance of somatic mutations identified in HLA genes.

bioinformatics↗

Immuno-genomic PanCancer Landscape Reveals Diverse Immune Escape Mechanisms and Immuno-Editing Histories

Immune reactions in the tumor micro-environment are one of the cancer hallmarks and emerging immune therapies have been proven effective in many types of cancer. To investigate cancer genome-immune interactions and the role of immuno-editing or immune escape mechanisms in cancer development, we analyzed 2,834 whole genomes and RNA-seq datasets across 31 distinct tumor types from the PanCancer Analysis of Whole Genomes (PCAWG) project with respect to key immuno-genomic aspects. We show that selective copy number changes in immune-related genes could contribute to immune escape. Furthermore, we developed an index of the immuno-editing history of each tumor sample based on the information of mutations in exonic regions and pseudogenes. Our immuno-genomic analyses of pan-cancer analyses have the potential to identify a subset of tumors with immunogenicity and diverse background or intrinsic pathways associated with their immune status and immuno-editing history.

genomics↗

ZMYND10 functions in a chaperone relay during axonemal dynein assembly

Molecular chaperones promote the folding and macromolecular assembly of a diverse set of substrate client proteins. How the ubiquitous chaperone machinery directs its activities towards a specific set of substrates and whether this selectivity could be targeted for therapeutic intervention is of intense research. Through the use of mouse genetics, imaging and quantitative proteomics we uncover that ZMYND10 is a novel co-chaperone for the FKBP8-HSP90 chaperone complex during the biosynthesis of axonemal dynein heavy chains required for cilia motility. In the absence of ZMYND10, defects in dynein heavy chains trigger broader dynein motor degradation. We show that FKBP8 inhibition phenocopies dynein motor instability in airway cells, and human disease-causing variants of ZMYND10 disrupt its ability to act as FKBP8-HSP90 co-chaperone. Our study indicates that the motile ciliopathy Primary Ciliary Dyskinesia (PCD) should be considered a cell-type specific protein-misfolding disease and opens the potential for rational drug design that could restore specificity to the ubiquitous chaperone apparatus towards dynein subunits.

cell biology↗