The Experts below are selected from a list of 261 Experts worldwide ranked by ideXlab platform

Hiroyuki Kaneko - One of the best experts on this subject based on the ideXlab platform.

  • Starfish ApDOCK protein essentially functions in larval defense system operated by Mesenchyme cells.
    Immunology and Cell Biology, 2012
    Co-Authors: Ryohei Furukawa, Midori Matsumoto, Hiromi Funabashi, Hiroyuki Kaneko
    Abstract:

    In larvae of the starfish, Asterina pectinifera, Mesenchyme cells operate in the defense system through various behaviors. We have investigated Mesenchyme cell dynamics during the immune response by identifying ApDOCK, a new member of the DOCK180 superfamily protein. In 4-day-old bipinnaria larvae processed for morpholino oligonucleotide-mediated knockdown of ApDOCK, injection of inorganic foreign substances revealed that (1) Mesenchyme cells fail to undergo either directed migration toward a large oil-droplet or persistent spreading on the oil-droplet after contact; (2) neither uptake of micro-beads nor cell-to-cell fusion on the large oil-droplet differed from that of Mesenchyme cells from control larvae. Similar behaviors were also recorded in experiments where bacteria were injected. Under culture conditions, the expression level of ApDOCK mRNA was significantly associated with the immunological behavior of Mesenchyme cells. Apparently, the Mesenchyme cells from ApDOCK loss-of-function larvae exhibited insufficient lamellipodium formation via lack of fibrous form of actin organization at the leading edge. These results suggest that the migratory congregation and persistence of encapsulation of larval Mesenchyme cells are intracellularly regulated by ApDOCK protein, and this regulation is associated with organization of cytoskeletal actin.

  • Uneven distribution pattern and increasing numbers of Mesenchyme cells during development in the starfish, Asterina pectinifera.
    Development Growth & Differentiation, 2011
    Co-Authors: Hamanaka, Eri Hosaka, Ritsu Kuraishi, Natsumi Hosoya, Midori Matsumoto, Hiroyuki Kaneko
    Abstract:

    During development, the embryos and larvae of the starfish Asterina pectinifera possess a single type of Mesenchyme cell. The aim of this study was to determine the patterns of behavior of Mesenchyme cells during the formation of various organs. To this end, we used a monoclonal antibody (Mesenchyme cell marker) to identify the distribution patterns and numbers of Mesenchyme cells. Our results revealed the following: (i) Mesenchyme cell behavior differs in the formation of different organs, showing temporal variations and an uneven pattern of distribution; and (ii) Mesenchyme cells continue to be generated throughout development, and their numbers are tightly regulated in proportion to total cell numbers.

  • Mesenchyme cells can function to induce epithelial cell proliferation in starfish embryos.
    Developmental Dynamics, 2010
    Co-Authors: Hamanaka, Midori Matsumoto, Masaya Imoto, Hiroyuki Kaneko
    Abstract:

    Here, we show that Mesenchyme cells have a novel morphogenetic function in epithelial cell proliferation in starfish embryos. Blastula embryos were injected with pure populations of Mesenchyme cells and the total cell numbers in the treated embryos were subsequently determined at different developmental stages. When a total of 40–50 Mesenchyme cells was injected, total cells numbers in mid-gastrula embryos and 3-day-old bipinnaria larvae increased significantly (by 1.3-fold) compared with controls, with no indication of any mitotic activity in the injected Mesenchyme cells. However, injection of more than 150 Mesenchyme cells failed to induce proliferation of the epithelial cells and, moreover, interfered with normal morphogenesis. These developmental abnormalities occurred concomitantly with a severe condensation of the fibrous component of the extracellular matrix. Our data suggest that epithelial cell proliferation is induced by an appropriate number of Mesenchyme cells in concert with the fibrous component of the extracellular matrix. Developmental Dynamics 239:818–827, 2010. © 2010 Wiley-Liss, Inc.

  • Defense system by Mesenchyme cells in bipinnaria larvae of the starfish, Asterina pectinifera
    Developmental and Comparative Immunology, 2008
    Co-Authors: Ryohei Furukawa, Yuko Takahashi, Yoko Nakajima, Marina Dan-sohkawa, Hiroyuki Kaneko
    Abstract:

    Here we characterize starfish larval Mesenchyme cells, in terms of not only their phagocytic behavior, but also their structural and functional properties as a defense system. Our study reveals the following: (1) most Mesenchyme cells construct a dynamic network structure beneath the body wall; (2) Mesenchyme cells phagocytically respond to almost all foreign materials and form syncytial aggregates to conceal relatively large amounts and large sizes of foreign material; (3) the morphologies of the syncytial aggregates differ from one another depending on the species and the surface configuration of the cellular foreign material; (4) no Mesenchyme cells respond to live Mesenchyme cells even though they phagocytose chemically fixed cells; (5) Mesenchyme cells phagocytose both cellular constituents effluxed from the ectodermal cells and foreign materials taken into the blastocoel through the body wall. Together, these results suggest that Mesenchyme cells are equipped with a spectrum of abilities to engage in a defense system in starfish larva.

Itzhak D Goldberg - One of the best experts on this subject based on the ideXlab platform.

Kenneth D Irvine - One of the best experts on this subject based on the ideXlab platform.

  • fat4 dchs1 signaling between stromal and cap Mesenchyme cells influences nephrogenesis and ureteric bud branching
    Development, 2015
    Co-Authors: Yaopan Mao, Philippa Franciswest, Kenneth D Irvine
    Abstract:

    Formation of the kidney requires reciprocal signaling among the ureteric tubules, cap Mesenchyme and surrounding stromal Mesenchyme to orchestrate complex morphogenetic events. The protocadherin Fat4 influences signaling from stromal to cap Mesenchyme cells to regulate their differentiation into nephrons. Here, we characterize the role of a putative binding partner of Fat4, the protocadherin Dchs1. Mutation of Dchs1 in mice leads to increased numbers of cap Mesenchyme cells, which are abnormally arranged around the ureteric bud tips, and impairment of nephron morphogenesis. Mutation of Dchs1 also reduces branching of the ureteric bud and impairs differentiation of ureteric bud tip cells into trunk cells. Genetically, Dchs1 is required specifically within cap Mesenchyme cells. The similarity of Dchs1 phenotypes to stromal-less kidneys and to those of Fat4 mutants implicates Dchs1 in Fat4-dependent stroma-to-cap Mesenchyme signaling. Antibody staining of genetic mosaics reveals that Dchs1 protein localization is polarized within cap Mesenchyme cells, where it accumulates at the interface with stromal cells, implying that it interacts directly with a stromal protein. Our observations identify a role for Fat4 and Dchs1 in signaling between cell layers, implicate Dchs1 as a Fat4 receptor for stromal signaling that is essential for kidney development, and establish that vertebrate Dchs1 can be molecularly polarized in vivo.

Andrew P Mcmahon - One of the best experts on this subject based on the ideXlab platform.

  • Transcriptional Regulation of the Nephrogenic Mesenchyme and Its Progeny
    Kidney Development Disease Repair and Regeneration, 2015
    Co-Authors: Jooseop Park, Andrew P Mcmahon
    Abstract:

    The nephrogenic Mesenchyme, or capping Mesenchyme, is a reservoir of stem/progenitor cells for kidney development. At each round of branching of the neighboring ureteric epithelium, cells within the nephrogenic Mesenchyme decide to remain uncommitted progenitors or to differentiate into renal vesicles (RV), the epithelial precursor unit that gives rise to each nephron. The Six2 transcription factor is required for the nephrogenic Mesenchyme to maintain its progenitor status, whereas Wnt9b/β-catenin signaling initiates its differentiation. Genome-wide mapping of Six2 and β-catenin interactions at the DNA level revealed a complex interplay in the action of these factors in controlling cell decision making within the nephrogenic Mesenchyme. Several lines of evidence have also linked a number of other regulatory factors, including Hox, Osr, Sall, and Wt family members, to these regulatory networks. Furthermore, genetic studies have highlighted the central role of Notch signaling, and the regional activity of a number of transcriptional factors including Lhx1, Pou3f3, Hnf1b, Mafb, and Tcf21 in subdividing RV derivatives into the physiologically distinct nephron segments that underpin nephron function.

  • wnt9b plays a central role in the regulation of mesenchymal to epithelial transitions underlying organogenesis of the mammalian urogenital system
    Developmental Cell, 2005
    Co-Authors: Thomas J. Carroll, Jooseop Park, Shigemi Hayashi, Arindam Majumdar, Andrew P Mcmahon
    Abstract:

    The vertebrate urogenital system forms due to inductive interactions between the Wolffian duct, its derivative the ureteric bud, and their adjacent Mesenchymes. These establish epithelial primordia within the mesonephric (embryonic) and metanephric (adult) kidneys and the Mullerian duct, the anlage of much of the female reproductive tract. We show that Wnt9b is expressed in the inductive epithelia and is essential for the development of mesonephric and metanephric tubules and caudal extension of the Mullerian duct. Wnt9b is required for the earliest inductive response in metanephric Mesenchyme. Further, Wnt9b-expressing cells can functionally substitute for the ureteric bud in these interactions. Wnt9b acts upstream of another Wnt, Wnt4, in this process, and our data implicate canonical Wnt signaling as one of the major pathways in the organization of the mammalian urogenital system. Together these findings suggest that Wnt9b is a common organizing signal regulating diverse components of the mammalian urogenital system.

Eliot M. Rosen - One of the best experts on this subject based on the ideXlab platform.