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Takeda, H.

Publications and source records attributed to Takeda, H..

3 recordsLinked to original sources

CTCF looping is established during gastrulation in medaka embryos

AbstractGenome architecture plays a critical role in gene regulation, but how the structures seen in mature cells emerge during embryonic development remains poorly understood. Here, we study early development in medaka (the Japanese killifish, Oryzias latipes) at 12 time points before, during, and after gastrulation which is the most dramatic event in early embryogenesis, and characterize transcription, protein binding, and genome architecture. We find that gastrulation is most associated with drastic changes in genome architecture, including the formation of the first loops between sites bound by the insulator protein CTCF and great increase in the size of contact domains. However, the position of CTCF is fixed throughout medaka embryogenesis. Interestingly, genome-wide transcription precedes the emergence of mature domains and CTCF-CTCF loops.

genomics

Systematic studies of all PIH proteins in zebrafish reveal their distinct roles in axonemal dynein assembly

Construction of motile cilia/flagella requires cytoplasmic preassembly of axonemal dyneins before transport into cilia. Axonemal dyneins have various subtypes, but the roles of each dynein subtype and their assembly processes remain elusive in vertebrates. The PIH protein family, consisting of four members, has been implicated in the assembly of different dynein subtypes, although evidence for this idea is sparse. Here, we established zebrafish mutants of all four PIH-protein genes: pih1d1, pih1d2, ktu, and twister, and analyzed the structures of axonemal dyneins in mutant spermatozoa by cryo-electron tomography. Mutations caused the loss of specific dynein subtypes, which was correlated with abnormal sperm motility. We also found organ-specific compositions of dynein subtypes, which could explain the severe motility defects of mutant Kupffers vesicle cilia. Our data demonstrate that all vertebrate PIH proteins are differently required for cilia/flagella motions and the assembly of axonemal dyneins, assigning specific dynein subtypes to each PIH protein.

cell biology

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