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131.
Kosei Tanaka Daisuke Matsumaru Kentaro Suzuki Gen Yamada Shinichi Miyagawa 《Development, growth & differentiation》2023,65(2):132-140
Embryonic external genitalia (genital tubercle [GT]) protrude from the cloaca and outgrow as cloacal development progresses. Individual gene functions and knockout phenotypes in GT development have been extensively analyzed; however, the interactions between these genes are not fully understood. In this study, we investigated the role of p63, focusing on its interaction with the Shh–Wnt/Ctnnb1–Fgf8 pathway, a signaling network that is known to play a role in GT outgrowth. p63 was expressed in the epithelial tissues of the GT at E11.5, and the distal tip of the GT predominantly expressed the ΔNp63α isoform. The GTs in p63 knockout embryos had normal Shh expression, but CTNNB1 protein and Fgf8 gene expression in the distal urethral epithelium was decreased or lost. Constitutive expression of CTNNB1 in p63-null embryos restored Fgf8 expression, accompanied by small bud structure development; however, such bud structures could not be maintained by E13.5, at which point mutant GTs exhibited severe abnormalities showing a split shape with a hemorrhagic cloaca. Therefore, p63 is a key component of the signaling pathway that triggers Fgf8 expression in the distal urethral epithelium and contributes to GT outgrowth by ensuring the structural integrity of the cloacal epithelia. Altogether, we propose that p63 plays an essential role in the signaling network for the development of external genitalia. 相似文献
132.
Human intestinal Caco-2 cells were cultured under serum-free conditions on an insoluble collagen and FCS matrix (Caco-2-SF), and a comparison was made between several characteristics of Caco-2 and Caco-2-SF cells. Their morphological appearance was identical. Slight differences were found in cell growth and expression of brush border enzymes between Caco-2 and Caco-2-SF cells. Similar levels of activity of Gly-Gly transport were expressed in both types of cell. Caco-2 cells cultured on permeable filters showed high transepithelial electrical resistance (TEER), indicating the high monolayer integrity. The transepithelial transport activity for glucose, alanine and Gly-Gly was detected by measuring the change in short-circuit current (Isc) after adding each of these nutrients to the apical chamber. In Caco-2-SF cells, such parameters as TEER and Isc were reduced drastically, suggesting that the monolayer integrity and cell polarity that are important for transepithelial transport were not attained. These parameters, however, could be restored by adding FCS or by milk whey. The result suggested that FCS and milk whey contain factors which regulate the formation of the tight junctions and, consequently, the development of cell polarity. Thus the Caco-2-SF cell-culture system will provide a useful model for studying factors which regulate the intestinal transepithelial transport functions.Abbreviations BCECF
2,7-bis(carboxyethyl)-5(6)-carboxyfluorescein
- TEER
transepithelial electrical resistance
- LY
lucifer yellow CH lithium salt 相似文献
133.
Shimizu Tsutomu; Hashimoto Naoya; Nakayama Ishizue; Nakao Tohru; Mizutani Hiroyuki; Unai Tadaaki; Yamaguchi Mikio; Abe Hiroshi 《Plant & cell physiology》1995,36(4):625-632
A novel isourazole herbicide, fluthiacet-methyl (methyl [[2-chloro-4-fluoro-5-[(5,6,7,8-tetrahydro-3-oxo-lH,3H-[l,3,4]thiadiazolo[3,4-a]pyridazin-l-ylidene)amino]phenyrjthio]acetate;experimental code name, KIH-9201) promoted the leakage of electrolytesfrom cotyledons of velvetleaf (Abtilon theophtasti Medic) andcotton (Gossypium hirsutum L.) plants that are sensitive tothis compound. It induced the accumulation of protoporphyrinIX in cotyledons of cotton and inhibited Chl biosynthesis incotyledons of velvetleaf and cotton at low concentrations (I50values, 1012 nM). Fluthiacet-methyl was converted toits urazole by glutathione S-transferase that had been partiallypurified from velvetleaf. The urazole inhibited protoporphyrinogenoxidase (Protox, EC 1.3.3.4
[EC]
) from some plants, including velvetleaf,at low concentrations (I50 values, 5.111 nM), whereasfluthiacet-methyl was not as potent. The effects in vivo (electrolyteleakage and inhibition of Chi biosynthesis) of fluthiacet-methylwere correlated with the inhibition of Protox activity by theurazole and not with the action of fluthiacet-methyl itself.From these results, it is concluded that fluthiacet-methyl inhibitsProtox activity after conversion to the corresponding urazoleby glutathione S-transferase. It is in this way that fluthiacet-methylexerts its effect as a light-dependent peroxidizing herbicide. (Received November 1, 1994; Accepted March 6, 1995) 相似文献
134.
Petunia guarapuavensis (Solanaceae): A new species from planalto of Paraná and Santa Catarina,Brazil
Petunia guarapuavensis, a new species fromplanalto (high plateau) of Paraná and Santa Catarina in Brazil, is described, and its morphological distinction from related species, features of the habitats, and geographical distribution are discussed. 相似文献
135.
136.
Ayako Yamamoto Tetsuo Hashimoto Emiko Asaga Masami Hasegawa Nobuichi Goto 《Journal of molecular evolution》1997,44(1):98-105
Major parts of amino-acid-coding regions of elongation factor (EF)-1α and EF-2 in Trichomonas tenax were amplified by PCR from total genomic DNA and the products were cloned into a plasmid vector, pGEM-T. The three clones
from each of the products of the EF-1α and EF-2 were isolated and sequenced. The insert DNAs of the clones containing EF-1α
coding regions were each 1,185 bp long with the same nucleotide sequence and contained 53.1% of G + C nucleotides. Those of
the clones containing EF-2 coding regions had two different sequences; one was 2,283 bp long and the other was 2,286 bp long,
and their G + C contents were 52.5 and 52.9%, respectively. The copy numbers of the EF-1α and EF-2 gene per chromosome were
estimated as four and two, respectively.
The deduced amino acid sequences obtained by the conceptual translation were 395 residues from EF-1α and 761 and 762 residues
from the EF-2s. The sequences were aligned with the other eukaryotic and archaebacterial EF-1αs and EF-2s, respectively.
The phylogenetic position of T. tenax was inferred by the maximum likelihood (ML) method using the EF-1α and EF-2 data sets. The EF-1α analysis suggested that
three mitochondrion-lacking protozoa, Glugea plecoglossi, Giardia lamblia, and T. tenax, respectively, diverge in this order in the very early phase of eukaryotic evolution. The EF-2 analysis also supported the
divergence of T. tenax to be immediately next to G. lamblia.
Received: 15 February 1996 / Accepted: 28 June 1996 相似文献
137.
138.
Localization of the B of L-hydroxyacid oxidase (HOX-B) in monkey kidney peroxisomes was investigated by immunoelectron microscopic techniques. Kidneys of Japanese monkeys,Macaca fuscata, were fixed with 4% paraformaldehyde+0.25% glutaraldehyde and embedded in LR White resin. Thin sections were stained for HOX-B and catalase by the immunogold technique. HOX-B was localized in the marginal plates of normal peroxisomes and the dense bar of dumb-bellshaped peroxisomes. Catalase was detected in the matrix of normal peroxisomes and in the terminal dilatations of dumb-bell-shaped peroxisomes. There were no gold particles indicating presence of catalase associated with the marginal plates or with the dense bars. Immunoblot analysis of monkey kidney homogenate showed that HOX-B has a molecular mass of 42 kDa that was slightly larger than that of rat kidney HOX-B (39 kDa). The results show that the dense bar of dumb-bell-shaped peroxisomes in monkey kidney is composed of at least HOX-B and is a variation of the marginal plates. 相似文献
139.
Recommendations vary on whether blood pressures should be measured in the right or in the left arm because no frequency distributions for a pressure difference between the arms exist. We took a total of 12 blood pressure determinations in both arms of 174 elderly persons and analyzed the data by a least-squares components of variance method. The mean difference between the arms (right minus left) was 0.93 mm of mercury for systole and 0.70 mm of mercury for diastole. For systole the proportion of persons having arm pressure differences exceeding 10 mm of mercury is 1.4% and that exceeding 7.5 mm of mercury is 6.5%. For most people, the pressure difference between the arms is small. 相似文献
140.
Naomi Eguchi Yasuyoshi Watanabe Kazuko Kawanishi Yohei Hashimoto Osamu Hayaishi 《Archives of biochemistry and biophysics》1984,232(2):602-609
β-Carboline derivatives inhibited both indoleamine 2,3-dioxygenase and tryptophan 2,3-dioxygenase activities from various sources. Among them, norharman is most potent for both enzymes from mammalian sources. Kinetic studies revealed that norharman is uncompetitive (Ki = 0.12 mm) with l-tryptophan for rabbit intestinal indoleamine 2,3-dioxygenase, and linearly competitive (Ki = 0.29 mm) with l-tryptophan for mouse liver tryptophan 2,3-dioxygenase. In addition, some β-carbolines selectively inhibited one enzyme or the other. Pseudomonad tryptophan 2,3-dioxygenase was inhibited by a different spectrum of β-carbolines. Such a selective inhibition by the structure of substrate analogs is more evident by the use of indole derivatives. Indole-3-acetamide, indole-3-acetonitrile and indole-3-acrylic acid exhibited a potent inhibition for mammalian tryptophan 2,3-dioxygenase, while they moderately inhibited the pseudomonad enzyme. However, they showed no inhibition for indoleamine 2,3-dioxygenase. These results suggest the difference of the structures of the active sites among these enzymes from various sources. 相似文献