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81.
82.
Rho-associated kinase, a novel serine/threonine kinase, as a putative target for small GTP binding protein Rho. 总被引:23,自引:2,他引:21 下载免费PDF全文
T Matsui M Amano T Yamamoto K Chihara M Nakafuku M Ito T Nakano K Okawa A Iwamatsu K Kaibuchi 《The EMBO journal》1996,15(9):2208-2216
The small GTP binding protein Rho is implicated in cytoskeletal responses to extracellular signals such as lysophosphatidic acid to form stress fibers and focal contacts. Here we have purified a Rho-interacting protein with a molecular mass of approximately 164 kDa (p164) from bovine brain. This protein bound to GTPgammaS (a non-hydrolyzable GTP analog).RhoA but not to GDP.RhoA or GTPgammaS.RhoA with a mutation in the effector domain (RhoAA37).p164 had a kinase activity which was specifically stimulated by GTPgammaS.RhoA. We obtained the cDNA encoding p164 on the basis of its partial amino acid sequences and named it Rho-associated kinase (Rho-kinase). Rho-kinase has a catalytic domain in the N-terminal portion, a coiled coil domain in the middle portion and a zinc finger-like motif in the C-terminal portion. The catalytic domain shares 72% sequence homology with that of myotonic dystrophy kinase and the coiled coil domain contains a Rho-interacting interface. When COS7 cells were cotransfected with Rho-kinase and activated RhoA, some Rho-kinase was recruited to membranes. Thus it is likely that Rho-kinase is a putative target serine/threonine kinase for Rho and serves as a mediator of the Rho-dependent signaling pathway. 相似文献
83.
M. Nakano Y. Hoshino M. Mii 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,92(2):170-172
Hypocotyl-derived protoplasts of Dianthus barbatus that had been pretreated with iodoacetamide were fused electrically with cell suspension culture-derived protoplasts of Gypsophila paniculata that could divide to form callus but could not regenerate shoots under the culture conditions used in this study. Electrofusion-derived calli which produced shoots were selected as putative somatic hybrids, and plantlets were subsequently regenerated from 2 of these selected calli. These plantlets, which in vitro produced flowers precociously, were identified as intergeneric somatic hybrids by nuclear ribosomal DNA analysis. Normal plants have not been established up to the present. 相似文献
84.
Hirobumi Suzuki Yasushi Sato Shizuo Fujiyama Nobuyoshi Ohba 《Biochemical genetics》1996,34(5-6):191-200
Japanese fireflies of the subfamily Luciolinae are biochemically analyzed using 13 allozymes, and the phylogenetic relationships obtained from this analysis are compared with their flash communication systems. As a result, the Japanese Luciolinae can be divided into three groups.Hotaria parvula andH. tsushimana together withLuciola yayeyamana andL. kuroiwae from the first group, and they use the same communication system.L. lateralis, Curtos okinawana, andC. costipennis make up the second group, and their communication systems are also the same.L. cruciata makes up the last one, and its communication system is different from the other fireflies of Luciolinae. Therefore, their taxonomical arrangement and communication systems are not congruent. However, the genetic similarity deduced by allozymic analysis of the members of the Japanese Luciolinae is highly consistent with their flash communication systems. 相似文献
85.
A smut fungus onPrimula sieboldii was newly found in Japan and identified asUrocystis tranzscheliana by comparative morphology. This species causes systemic infection ofP. sieboldii and produces sori in its ovaries.Contribution No. 121, Laboratories of Plant Pathology and Mycology, Institute of Agriculture and Forestry, University of Tsukuba. 相似文献
86.
87.
Phorbol ester induces the rapid processing of cell surface heparin-binding EGF-like growth factor: conversion from juxtacrine to paracrine growth factor activity. 总被引:18,自引:1,他引:17 下载免费PDF全文
K Goishi S Higashiyama M Klagsbrun N Nakano T Umata M Ishikawa E Mekada N Taniguchi 《Molecular biology of the cell》1995,6(8):967-980
Vero cell heparin-binding epidermal growth factor-like growth factor (HB-EGF) is synthesized as a 20- to 30-kDa membrane-anchored HB-EGF precursor (proHB-EGF). Localization and processing of proHB-EGF, both constitutive and 12-O-tetradecanoylphorbol 13-acetate (TPA)-inducible, was examined in Vero cells overexpressing recombinant HB-EGF (Vero H cells). Flow cytometry and fluorescence immunostaining demonstrated that Vero cell proHB-EGF is cell surface-associated and localized at the interface of cell to cell contact. Cell surface biotinylation and immunoprecipitation detected a 20- to 30-kDa heterogeneous proHB-EGF species. Vero H cell surface proHB-EGF turned over constitutively with a half-life of 1.5 h. Some of the 20- to 30-kDa cell surface-associated proHB-EGF was processed and a 14-kDa species of bioactive HB-EGF was released slowly, but most of the proHB-EGF was internalized, displaying a diffuse immunofluorescent staining pattern and accumulation of proHB-EGF in endosomes. Addition of TPA induced a rapid processing of proHB-EGF at a Pro148-Val149 site with a half-life of 7min. The TPA effect was abrogated by the protein kinase C inhibitors, staurosporine and H7. Kinetic analysis showed that loss of cell surface proHB-EGF is maximal at 30 min after addition of TPA and that proHB-EGF is resynthesized and the initial cell surface levels are regained within 12-24 h. Loss of cell surface proHB-EGF was concomitant with appearance of 14- and 19-kDa soluble HB-EGF species in conditioned medium. Vero H cell-associated proHB-EGF is a juxtacrine growth factor for EP170.7 cells in coculture. Processing of proHB-EGF resulted in loss of juxtacrine activity and a simultaneous increase in soluble HB-EGF paracrine mitogenic activity. It was concluded that processing regulates HB-EGF bioactivity by converting it from a cell-surface juxtacrine growth factor to a processed, released soluble paracrine growth factor. 相似文献
88.
Purification and characterization of periplasmic alpha-amylase from Xanthomonas campestris K-11151. 下载免费PDF全文
J Abe N Onitsuka T Nakano Y Shibata S Hizukuri E Entani 《Journal of bacteriology》1994,176(12):3584-3588
Xanthomonas campestris K-11151, isolated from soil, produced a periplasmic alpha-amylase of a new type. The enzyme was purified to homogeneity, as shown by several criteria. The purified enzyme showed almost the same activities on alpha-, beta-, and gamma-cyclodextrins, soluble starch, and amylose. Moreover, it was active on branched cyclodextrins, pullulan, and maltose but not on glycogen. Kinetic analysis showed that alpha-cyclodextrin was the best substrate among the cyclodextrins. The substrate specificity suggested that this enzyme had the combined activities of alpha-amylase, cyclodextrinase, and neopullulanase. 相似文献
89.
Seasonal changes in the spermatogenic epithelium of adult Japanese macaques (Macaca fuscata fuscata)
Tomoo Enomoto Kiyoaki Matsubayashi Yasukazu Nagato Mayumi Nakano 《Primates; journal of primatology》1994,35(4):465-472
A histological study was undertaken to clarify seasonal changes in the spermatogenic epithelium of Japanese macaques. Testicular
tissue samples were excised by biopsies from five adult laboratory-maintained males in mating and non-mating seasons. The
samples were fixed with Bouin's solution, embedded in paraffin, and stained with PAS and hematoxylin. Microscopic observations
on cross-sections of seminiferous tubules revealed that the seminiferous epithelium in the mating season was thicker than
in the non-mating season. PAS-stained granules were found in some of the dark A-type spermatogonia, which significantly increased
in the non-mating season. Spermatids of the steps preceding the appearance of the acrosomic cap in stages I to III were observed
significantly more often than those in the step coinciding with the formation of the acrosomic cap in stage IV. In stage I,
the ratio of mature spermatids or spermatozoa to immature spermatids in the mating season was higher than that in the non-mating
season. These findings suggest that spermiogenesis, as well as spermatocytogenesis, is inhibited in the non-mating season. 相似文献
90.
Efficiency of serum copper/zinc ratio for differential diagnosis of patients with and without lung cancer 总被引:1,自引:0,他引:1
Tsunehiro Oyama Koji Matsuno Toshihiro Kawamoto Tetsuya Mitsudomi Takayuki Shirakusa Yasushi Kodama 《Biological trace element research》1994,42(2):115-127
We examined serum copper (Cu), serum zinc (Zn), and the serum copper/zinc ratio (Cu/Zn) in 162 patients. All of them were
seen to have an abnormal shadow in the chest X-ray films, that is, 109 patients with lung cancer (LC) and 53 patients with
no lung cancer (NLC). The mean Cu and Cu/Zn in LC patients were significantly higher than those in NLC patients (p<0.05). In LC patients, Cu and Cu/Zn were higher and Zn was lower in advanced tumors than early ones. There was a significantly
clear relation between Cu or Cu/Zn and the tumor (T) stages. When the relative risk (RR) of LC was estimated, it was seen
that the higher Cu and Cu/Zn became, the higher RR became. Furthermore, we showed the sensitivity of the receiver operator
characteristic of the test (ROC) curve for Cu, Cu/Zn, and carcinoembryonic antigen (CEA) to diagnose LC, as explained in a
paragraph of methods.The determinations of Cu, Zn, and Cu/Zn are simple and inexpensive. They also appear to have a great diagnostic value in determining the local invasion of LC and as a screening test in the
high-risk patients for LC. 相似文献