The Experts below are selected from a list of 240 Experts worldwide ranked by ideXlab platform
Nancy A Speck - One of the best experts on this subject based on the ideXlab platform.
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energetic contribution of residues in the runx1 runt domain to dna binding
Journal of Biological Chemistry, 2003Co-Authors: Zhe Li, Christina J Matheny, Takeshi Corpora, Alan J Warren, Jerónimo Bravo, John H Bushweller, Nancy A SpeckAbstract:Abstract Core-binding factors (CBFs) are a small family of heterodimeric transcription factors that play critical roles in hematopoiesis and in the development of bone, Stomach Epithelium, and proprioceptive neurons. Mutations in CBF genes are found in leukemias, bone disorders, and gastric cancer. CBFs consist of a DNA-binding CBFα subunit and a non-DNA-binding CBFβ subunit. DNA binding and heterodimerization with CBFβ are mediated by the Runt domain in CBFα. Here we report an alanine-scanning mutagenesis study of the Runt domain that targeted amino acids identified by structural studies to reside at the DNA or CBFβ interface, as well as amino acids mutated in human disease. We determined the energy contributed by each of the DNA-contacting residues in the Runt domain to DNA binding both in the absence and presence of CBFβ. We propose mechanisms by which mutations in the Runt domain found in hematopoietic and bone disorders affect its affinity for DNA.
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Energetic Contribution of Residues in the Runx1 Runt Domain to DNA Binding
The Journal of biological chemistry, 2003Co-Authors: Jiangli Yan, Christina J Matheny, Takeshi Corpora, Alan J Warren, Jerónimo Bravo, John H Bushweller, Nancy A SpeckAbstract:Core-binding factors (CBFs) are a small family of heterodimeric transcription factors that play critical roles in hematopoiesis and in the development of bone, Stomach Epithelium, and proprioceptive neurons. Mutations in CBF genes are found in leukemias, bone disorders, and gastric cancer. CBFs consist of a DNA-binding CBF alpha subunit and a non-DNA-binding CBF beta subunit. DNA binding and heterodimerization with CBF beta are mediated by the Runt domain in CBF alpha. Here we report an alanine-scanning mutagenesis study of the Runt domain that targeted amino acids identified by structural studies to reside at the DNA or CBF beta interface, as well as amino acids mutated in human disease. We determined the energy contributed by each of the DNA-contacting residues in the Runt domain to DNA binding both in the absence and presence of CBF beta. We propose mechanisms by which mutations in the Runt domain found in hematopoietic and bone disorders affect its affinity for DNA.
Sadao Yasugi - One of the best experts on this subject based on the ideXlab platform.
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FGF10 is required for cell proliferation and gland formation in the Stomach Epithelium of the chicken embryo
Developmental biology, 2006Co-Authors: Masahiro Shin, Sumihare Noji, Annette Neubüser, Sadao YasugiAbstract:The development of digestive organs in vertebrates involves active epithelial–mesenchymal interactions. In the chicken proventriculus (glandular Stomach), the morphogenesis and cytodifferentiation of the Epithelium are controlled by the inductive signaling factors that are secreted from the underlying mesenchyme. Previous studies have shown that Fgf10 is expressed in the developing chicken proventricular mesenchyme, whereas its receptors are present in the Epithelium. In our present study, we show that FGF10 is an early mesenchymal signal that is critically associated with the developmental processes in the proventricular Epithelium. Furthermore, virus-mediated Fgf10 overexpression in ovo results in a hypermorphic epithelial structure and an increase in epithelial cell number. In contrast, the overexpression of a secreted FGFR2b (sFGFR2b), an FGF10 antagonist, blocks cell proliferation and gland formation in the proventricular Epithelium in ovo. This downregulation of proliferative activity was subsequently found to retard gland formation and also to delay differentiation of the Epithelium. These results demonstrate that FGF10 signaling, mediated by FGFR1b and/or FGFR2b, is required for proliferation and gland formation in the Epithelium in the developing chick embryo.
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Application of efficient and specific gene transfer systems and organ culture techniques for the elucidation of mechanisms of epithelial– mesenchymal interaction in the developing gut
Development growth & differentiation, 2000Co-Authors: Kimiko Fukuda, Nobuyuki Sakamoto, Tomohiro Narita, Kanako Saitoh, Takashi Kameda, Hideo Iba, Sadao YasugiAbstract:Epithelial–mesenchymal interactions are very important in the development of the vertebrate gut. In the avian embryonic Stomach (proventriculus), expression of embryonic chick pepsinogen (ECPg) gene, which is specific to developing glandular cells in Stomach Epithelium, is regulated by mesenchymal influence. Molecular mechanisms of tissue-specific transcriptional regulation of the ECPg gene and the molecular nature of the mesenchymal signals were analyzed using a combination of the classic organ culture system and gene transfer strategies. In the present review, three methods for the introduction of DNA into tissues are described: lipofection, electroporation and retroviral infection, and characteristics of each system are discussed.
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tissue interaction regulates expression of a spasmolytic polypeptide gene in chicken Stomach Epithelium
Development Growth & Differentiation, 1998Co-Authors: Hidenori Tabata, Sadao YasugiAbstract:: The primitive Epithelium of embryonic chicken proventriculus (glandular Stomach) differentiates, after day 6 of incubation, into luminal Epithelium, which faces the lumen and abundantly secretes mucus, and glandular Epithelium, which invaginates into mesenchyme and later expresses embryonic chicken pepsinogen (ECPg). So far it is not well understood how undifferentiated epithelial cells differentiate into these two distinct cell populations. Spasmolytic polypeptide (SP) is known to be expressed in surface mucous cells of mammalian Stomach. In order to obtain the differentiation marker for proventricular luminal epithelial cells, we cloned a cDNA encoding chicken SP (cSP). Sequence analysis indicated that cSP has the duplicated cysteine-rich domain characteristic of SP. Examination of the spatial and temporal expression pattern of cSP gene revealed that, during embryogenesis, cSP was expressed in lumina epithelial cells of the proventriculus, gizzard, small intestine, and lung, but not the esophagus. In the proventriculus, cSP mRNA was first detected on day 8 of incubation and was localized to differentiated luminal epithelial cells. By using cSP as a molecular marker, the effects of mesenchyme on the differentiation of Epithelium were analyzed in vitro. On the basis of these data, a model is presented concerning the differentiation of proventricular Epithelium.
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Localization of DNA-synthesizing cells and cell proliferation pattern in developing proventricular (glandular Stomach) Epithelium of embryonic and hatched chickens
Development Growth and Differentiation, 1996Co-Authors: Da-yun Jin, Yasuo Ishii, Sadao YasugiAbstract:Localization of DNA-synthesizing cells in the developing proventricular (glandular Stomach) Epithelium of embryonic and hatched chickens was investigated. DNA-synthesizing cells were scattered throughout the proventricular Epithelium during all developmental stages studied. The results indicate that there is no clear proliferative zone in the proventricular Epithelium of the chicken. The labeling indices (LI) of proventricular epithelial cells were measured. On the 6.5th day of incubation, the LI of glandular Epithelium reached 29.5 ± 1.5%. the highest value of all the stages studied. This extremely rapid cell proliferation can be considered to be a driving force for the elongation of the proventricular glands during the following stages. Just after hatching, the LI of both the glandular and luminal (non-glandular) epithelia significantly increased from those on the 18th day of incubation. It is suggested that the rise in LI possibly reflected proventricular growth to fit in the change in the method of nourishment after hatching. In 2 week old chickens, the LI of both the glandular and luminal epithelia were reduced to approximately 1%. The active production of embryonic chicken pepsinogen in all glandular epithelial cells of the embryonic chicken revealed that proliferation and differentiation are not necessarily exclusive during the embryonic stages of proventricular development.
Jessica H. Geahlen - One of the best experts on this subject based on the ideXlab platform.
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Differentiated Troy+ Chief Cells Act as Reserve Stem Cells to Generate All Lineages of the Stomach Epithelium
Cell, 2013Co-Authors: Daniel E. Stange, Bon-kyoung Koo, Meritxell Huch, Greg Sibbel, Onur Basak, Anna Lyubimova, Pekka Kujala, Sina Bartfeld, Jan Koster, Jessica H. GeahlenAbstract:Proliferation of the self-renewing Epithelium of the gastric corpus occurs almost exclusively in the isthmus of the glands, from where cells migrate bidirectionally toward pit and base. The isthmus is therefore generally viewed as the stem cell zone. We find that the stem cell marker Troy is expressed at the gland base by a small subpopulation of fully differentiated chief cells. By lineage tracing with a Troy-eGFP-ires-CreERT2 allele, single marked chief cells are shown to generate entirely labeled gastric units over periods of months. This phenomenon accelerates upon tissue damage. Troy(+) chief cells can be cultured to generate long-lived gastric organoids. Troy marks a specific subset of chief cells that display plasticity in that they are capable of replenishing entire gastric units, essentially serving as quiescent "reserve" stem cells. These observations challenge the notion that stem cell hierarchies represent a "one-way street."
Jianzhong Zhu - One of the best experts on this subject based on the ideXlab platform.
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Isolation and dynamic distribution of white spot syndrome virus Sheyang strain in crawfishes
Journal of Nanjing Agricultural University, 2002Co-Authors: Jianzhong ZhuAbstract:Died shrimps collected from a shrimp farm in 1999 in Sheyang,Jiangsu Province,were homogenized and taken to inoculate crawfishes.The infected crawfishes all died within 4?8 days and the crawfishes inoculated with tissue supernatant of the died crawfishes also died within 6?8 days.The tissue samples of died shrimps and crawfishes were all positive of white spot syndrome virns(WSSV) in MAb mediated ELISA and Dot blot,so the isolated virus was designated as WSSV Sheyang strain.The dynamic distribution of the WSSV Sheyang strain in crawfishes was studied and compared to that of WSSV Qingdao strain.WSSV was first detected in heamolymph at 12 h p i in both oral infection and injection group and decreased.At 36 h p i ,WSSV was obviously detected once again,increasing to maximum amount and then declining.WSSV in intestine Epithelium,heart and muscle of both groups was detected at 36 h p i and increased generally.In addition,WSSV in Stomach Epithelium,hypoderm,connective tissue of oral infection group and Stomach Epithelium,hypoderm of injection group could be also detected.In died shrimp,WSSV could be detected in all the examined tissues by Dot blot,ELISA and EM,suggesting systemic infection had occurred.It suggested the dynamic distribution of the WSSV Sheyang strain in crawfishes was similar to that of Qingdao strain.
Christina J Matheny - One of the best experts on this subject based on the ideXlab platform.
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energetic contribution of residues in the runx1 runt domain to dna binding
Journal of Biological Chemistry, 2003Co-Authors: Zhe Li, Christina J Matheny, Takeshi Corpora, Alan J Warren, Jerónimo Bravo, John H Bushweller, Nancy A SpeckAbstract:Abstract Core-binding factors (CBFs) are a small family of heterodimeric transcription factors that play critical roles in hematopoiesis and in the development of bone, Stomach Epithelium, and proprioceptive neurons. Mutations in CBF genes are found in leukemias, bone disorders, and gastric cancer. CBFs consist of a DNA-binding CBFα subunit and a non-DNA-binding CBFβ subunit. DNA binding and heterodimerization with CBFβ are mediated by the Runt domain in CBFα. Here we report an alanine-scanning mutagenesis study of the Runt domain that targeted amino acids identified by structural studies to reside at the DNA or CBFβ interface, as well as amino acids mutated in human disease. We determined the energy contributed by each of the DNA-contacting residues in the Runt domain to DNA binding both in the absence and presence of CBFβ. We propose mechanisms by which mutations in the Runt domain found in hematopoietic and bone disorders affect its affinity for DNA.
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Energetic Contribution of Residues in the Runx1 Runt Domain to DNA Binding
The Journal of biological chemistry, 2003Co-Authors: Jiangli Yan, Christina J Matheny, Takeshi Corpora, Alan J Warren, Jerónimo Bravo, John H Bushweller, Nancy A SpeckAbstract:Core-binding factors (CBFs) are a small family of heterodimeric transcription factors that play critical roles in hematopoiesis and in the development of bone, Stomach Epithelium, and proprioceptive neurons. Mutations in CBF genes are found in leukemias, bone disorders, and gastric cancer. CBFs consist of a DNA-binding CBF alpha subunit and a non-DNA-binding CBF beta subunit. DNA binding and heterodimerization with CBF beta are mediated by the Runt domain in CBF alpha. Here we report an alanine-scanning mutagenesis study of the Runt domain that targeted amino acids identified by structural studies to reside at the DNA or CBF beta interface, as well as amino acids mutated in human disease. We determined the energy contributed by each of the DNA-contacting residues in the Runt domain to DNA binding both in the absence and presence of CBF beta. We propose mechanisms by which mutations in the Runt domain found in hematopoietic and bone disorders affect its affinity for DNA.