Publications by authors named "Yoshikazu Haramoto"

Fusion among normal cells is tightly regulated and required for the developmental processes of an organism. Cancer cell fusion appears relatively rare but is associated with generating new hybrid cancer cells with aggressive properties. However, it remains unclear how cancer cells acquire aggressiveness via cell fusion.

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The zinc finger and BTB domain-containing 11 gene (zbtb11) is expressed in the Xenopus anterior neuroectoderm, but the molecular nature of the Zbtb11 protein during embryonic development remains to be elucidated. Here, we show the role of Zbtb11 in anterior patterning of the neuroectoderm and the cooperative action with the transcription factor Otx2. Both overexpression and knockdown of zbtb11 caused similar phenotypes: expanded expression of the posterior gene gbx2 in the neural plate, and later microcephaly with reduced eyes, suggesting that a proper level of zbtb11 expression is necessary for normal patterning of the neuroectoderm, including eye formation.

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Overproduction of isopentenyl diphosphate by the amplification of the genes for the methylerythritol 4-phosphate pathway, dxs and dxr, is known to be deleterious for the growth of Escherichia coli. We hypothesized that overproduction of one of the endogenous isoprenoids, in addition to isopentenyl diphosphate itself, might be the cause of the reported reduced growth rate and attempted to identify the causative agent. In order to analyze polyprenyl phosphates, they were methylated by the reaction with diazomethane.

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Protein evolution rate is negatively correlated with several effectors, such as expression level, expression distribution, protein-protein interactions (PPIs), and essentiality for survival. These effectors can characterize the signaling pathways mediated by ligand-receptor binding. However, it is unclear whether these effectors are constraining factors on the pathway-specific evolution of ligands and receptors.

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X chromosome inactivation (XCI), determined during development, remains stable after embryonic cell divisions. However, primordial germ cells (PGCs) are exceptions in that XCI is reprogrammed and inactivated X chromosomes are reactivated. Although interactions between PGCs and somatic cells are thought to be important for PGC development, little is known about them.

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Foam nests of frogs are natural biosurfactants that contain potential compounds for biocompatible materials, Drug Delivery System (DDS), emulsifiers, and bioremediation. To elucidate the protein components in the foam nests of , which is an endemic Japanese frog species commonly seen during the rainy season, we performed amino acid analysis, SDS-PAGE electrophoresis, and matrix-assisted laser desorption/ionization mass spectrometry using intact foam nests. Many proteins were detected in these foam nests, ranging from a few to several hundred kDa, with both essential and non-essential amino acids.

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We determined the complete mitochondrial genome sequence of the Japanese forest green tree frog (). The mitochondrial genome is 22,236 bp in length, which encodes 13 protein-coding genes, 2 rRNA, and 22 tRNA genes, and two control regions (D-loops). The whole gene arrangement of was the same as that of and .

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Quality control for human induced pluripotent stem cells (hiPSCs) is important for efficient and stable production of hiPSC-derived cell therapy products to be used for transplantation. During cell culture, hiPSCs spontaneously undergo morphological changes and lose pluripotent properties. Such cells are termed deviated cells, which are altered from the undifferentiated state of hiPSCs, and express the early differentiation marker stage-specific embryonic antigen 1 (SSEA-1).

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Introduction: Tumourigenesis attributed to residual undifferentiated cells in a graft is considered to be a significant issue in cell therapy using human pluripotent stem cells. To ensure the safety of regenerative medicine derived from pluripotent stem cells, residual undifferentiated cells must be eliminated in the manufacturing process. We previously described the lectin probe rBC2LCN, which binds harmlessly and specifically to the cell surface of human pluripotent stem cells.

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The recombinant N-terminal domain of BC2L-C lectin (rBC2LCN) is useful for detecting not only human pluripotent stem cells but also some cancers. However, the cancer types and stages that can be detected by rBC2LCN remain unclear. In this study, we identified the human breast carcinoma subtypes and stages that can be detected by rBC2LCN.

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In recent advanced information society, it is important to individually identify products or living organisms automatically and quickly. However, with the current identifying technology such as RFID tag or biometrics, it is difficult to apply to amphibians such as frogs or newts because of its size, stability, weakness under a wet environment and so on. Thus, this research aims to establish a system that can trace small amphibians easily even in a wet environment and keep stable sensing for a long time.

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Urodele newts have unique biological properties, notably including prominent regeneration ability. The Iberian ribbed newt, Pleurodeles waltl, is a promising model amphibian distinguished by ease of breeding and efficient transgenic and genome editing methods. However, limited genetic information is available for P.

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RecQ-like helicase 4 (RECQL4) is mutated in patients suffering from the Rothmund-Thomson syndrome, a genetic disease characterized by premature aging, skeletal malformations, and high cancer susceptibility. Known roles of RECQL4 in DNA replication and repair provide a possible explanation of chromosome instability observed in patient cells. Here, we demonstrate that RECQL4 is a microtubule-associated protein (MAP) localizing to the mitotic spindle.

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genes are found as clusters in the genome in most bilaterians. The order of genes in the cluster is supposed to be correlated with the site of expression along the anterior-posterior body axis and the timing of expression during development, and these correlations are called spatial and temporal collinearity, respectively. Here we studied the expression dynamics of all genes of the diploid species in four Hox clusters (A-D) by analyzing high-temporal-resolution RNA-seq databases and the results showed that temporal collinearity is not supported, which is consistent with our previous data from allotetraploid Because the temporal collinearity hypothesis implicitly assumes the collinear order of gene activation, not mRNA accumulation, we determined for the first time the timing of when new transcripts of genes are produced, by detecting pre-spliced RNA in whole embryos with reverse transcription and quantitative PCR (RT-qPCR) for all genes as well as several selected , and genes.

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To explore the origins and consequences of tetraploidy in the African clawed frog, we sequenced the Xenopus laevis genome and compared it to the related diploid X. tropicalis genome. We characterize the allotetraploid origin of X.

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Two siamois-related homeobox genes siamois (sia1) and twin (sia2), have been reported in Xenopus laevis. These genes are expressed in the blastula chordin- and noggin-expressing (BCNE) center and the Nieuwkoop center, and have complete secondary axis-inducing activity when over-expressed on the ventral side of the embryo. Using whole genome sequences of X.

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Pxt peptides (Pxt-1 through Pxt-12) have been isolated from amphibian, Xenopus tropicalis Pxt-related peptides (Pxt-2, Pxt-5, Pxt-12, reverse Pxt-2, reverse Pxt-5 and reverse Pxt-12) with significant foaming properties were further characterized. In the physicochemical experiments, all Pxt-related peptides formed significant amphiphilic α-helices in 50% 2,2,2-trifluoroethanol by circular dichroism measurements. Among Pxt-related peptides, both Pxt-5 and reverse Pxt-5 were the most effective in reducing their surface tensions.

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Insulin receptor (IR) and insulin-like growth factor-1 receptor (IGF1R) signalling is required for normal embryonic growth and development. Previous reports indicated that the IGF/IGF1R/MAPK pathway contributes to neural induction and the IGF/IGF1R/PI3K/Akt pathway to eye development. Here, we report the isolation of insulin3 encoding a novel insulin-like ligand involved in neural induction.

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The diploid Xenopus tropicalis, with its small nuclear genomic size and short generation time compared to the traditional experimental amphibian X. laevis, is considered a next-generation model animal. Several experimental X.

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Twelve novel peptides (Pxt-1 to Pxt-12) were isolated from the skin of Xenopus tropicalis, diploid frogs, using topological MS analysis. Among them, Pxt-8, Pxt-9, and Pxt-10 were the N terminus of Pxt-1, N terminus of Pxt-3 and C terminus of Pxt-11, respectively. The Pxt-3 and Pxt-11 peptides shared significant sequence homologies with magainins 1, -2 and levitide, respectively, which all isolated from X.

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Head specification by the head-selector gene, orthodenticle (otx), is highly conserved among bilaterian lineages. However, the molecular mechanisms by which Otx and other transcription factors (TFs) interact with the genome to direct head formation are largely unknown. Here we employ ChIP-seq and RNA-seq approaches in Xenopus tropicalis gastrulae and find that occupancy of the corepressor, TLE/Groucho, is a better indicator of tissue-specific cis-regulatory modules (CRMs) than the coactivator p300, during early embryonic stages.

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The insulin-like growth factor binding protein (Igfbp) family consists of six members designated Igfbp1-6. Igfbps are involved in many vital biological functions. They physically interact with IGFs (IGF1 and IGF2) and act as carriers, thereby protecting IGFs from proteolytic degradation.

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Neural induction and anteroposterior neural patterning occur simultaneously during Xenopus gastrulation by the inhibition of BMP and Wnt signaling, respectively. However, other processes might be necessary for determining the neural-epidermal boundary. Xenopus nodal-related-3 (Xnr3) is expressed in dorsal blastula and plays a role in neural formation.

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Hippo signaling is a conserved pathway that regulates cell proliferation and organ size control. Mst1 and Mst2 were identified as homologs of hippo and as core kinases of the Hippo pathway in mammals. Here, we have characterized the role of Mst1 and Mst2 during Xenopus primitive hematopoiesis.

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Steroid hormones play essential roles in a wide variety of biological processes in multicellular organisms. The principal steroid hormones in nematodes and arthropods are dafachronic acids and ecdysteroids, respectively, both of which are synthesized from cholesterol as an indispensable precursor. The first critical catalytic step in the biosynthesis of these ecdysozoan steroids is the conversion of cholesterol to 7-dehydrocholesterol.

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