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1.
A putative GDP–GTP exchange factor is required for development of the excretory cell in Caenorhabditis elegans 下载免费PDF全文
Norio Suzuki Matthew Buechner Kiyoji Nishiwaki David H. Hall Hiroyuki Nakanishi Yoshimi Takai Naoki Hisamoto Kunihiro Matsumoto 《EMBO reports》2001,2(6):530-535
The Caenorhabditis elegans excretory cell extends tubular processes, called canals, along the basolateral surface of the epidermis. Mutations in the exc-5 gene cause tubulocystic defects in this canal. Ultrastructural analysis suggests that exc-5 is required for the proper placement of cytoskeletal elements at the apical epithelial surface. exc-5 encodes a protein homologous to guanine nucleotide exchange factors and contains motif architecture similar to that of FGD1, which is responsible for faciogenital dysplasia. exc-5 interacts genetically with mig-2, which encodes Rho GTPase. These results suggest that EXC-5 controls the structural organization of the excretory canal by regulating Rho family GTPase activities. 相似文献
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Komeda Yoshibumi; Yamashita Hirofumi; Sato Naoki; Tsukaya Hirokazu; Naito Satoshi 《Plant & cell physiology》1991,32(6):737-743
The 5'-upstream region (2.4 kb) of the gene for phytochromeI from Pisum sativum (phyl) was fused to the uidA gene fromEscherichia coli that encodes ß-glucuronidase (GUS).The resulting PHY-GUS fusion was introduced into Petunia hybridaand was used as a reporter of the expression of the phyI genewhich was recognized by GUS activity. The PHY-GUS fusion wasexpressed at a relatively high level when transgenic plantswere grown in the dark, while leaves and stems of light-grownplants showed background activity. Flowers of light-grown plantswere shown to have significant levels of GUS activity but rootsdid not have such activity. When light-grown transgenic plantswere transferred to the dark, they expressed the activity atlevels that corresponded to those of dark-grown plants. Lighttreatment prior to growth in darkness revealed red/far-red reversibilityof recovery of the activity. Thus, the 2.4-kb fragment fromthe 5' region of the phyI gene carries the information necessaryfor the light-repressible autoregulation. (Received March 30, 1991; Accepted May 20, 1991) 相似文献
4.
Urinary excretion of isomers of biliverdin after destruction in vivo of haemoproteins and haemin. 下载免费PDF全文
The amount and isomeric composition of urinary biliverdin in rabbits were analysed by h.p.l.c. Physiological values were maintained after the injection of haemin. On the other hand, when haemoglobins from several mammalian species were injected into rabbits, the excretion of biliverdin-IX alpha and biliverdin-IX beta were increased 6-18-fold and 32-66-fold respectively over physiological excretion. Injection of myoglobin resulted in a 44-fold increase in excretion of the IX alpha-isomer. Coupled oxidation with ascorbate of haemoglobin and myoglobin by oxygen produced mainly the IX alpha- and IX beta-isomers from haemoglobin and the IX alpha-isomer from myoglobin. The destruction of part of the haem from injected haemoproteins by non-enzymic chemical degradation would account for the observed respective increases in the excretion of biliverdin isomers. The excretion of biliverdin isomers after the injection of phenylhydrazine into rabbits was similar to that after the injection of haemoglobin. 相似文献
5.
A photosystem other than PS370 also mediates the negative phototaxis of Halobacterium halobium 总被引:2,自引:0,他引:2
Tetsuo Takahashi Hiroaki Tomioka Naoki Kamo Yonosuke Kobatake 《FEMS microbiology letters》1985,28(2):161-164
Abstract It was found that a photorepellent system other than photosystem 370 (PS370) also controls the behavior of Halobacterium halobium . Both the dependence of background illumination and wavelength where the response showed maximum action distinguished that photosystem from PS370 whose photoreceptor pigment is thought to be an intermediate of s-rhodopsin (sR). A mutant strain that has no detectable activity in PS370 and in photoattractant response was isolated. This mutant strain showed the repellent response due to the new photosystem. 相似文献
6.
Sakurai Naoki; Inouhe Masahiro; Masuda Yoshio; Kuraishi Susumu 《Plant & cell physiology》1983,24(3):317-325
Sugar compositions of cell walls of dark-grown coleoptiles from12 barley strains, 11 of which were coleoptilar semi-dwarf strains,were analyzed on days 2 and 3 after germination. Major wallcomponents of the 12 strains were arabinose, xylose, and glucosein hemicellulose and cellulose; minor components were galactoseand mannose. The sugar content of each wall component per unit length wasnot correlated to any growth parameters calculated from a logisticequation simulating coleoptile growth, but the relative contentsof galactose and mannose in relation to the total wall sugarcontent was correlated to the growth rate on day 3 and the growthcontinuing period. These facts suggest that growth of these12 barley strains in the late growth stage is regulated by theminor wall components, galactose and mannose.
1 Dedicated to the late Professor Joji Ashida. (Received October 12, 1982; Accepted January 12, 1983) 相似文献
7.
H Nishio H Matsui L J Moia S Taketa K Miyamoto M Tokuda T Itano S Nakahara O Hatase 《Biochemical and biophysical research communications》1992,187(2):828-831
The expression of a regulatory subunit of calcineurin (CaN beta) during rat spermatogenesis was examined in rat testes using a monoclonal antibody Va1. Results showed that a testis-specific isoform of CaN beta was expressed only 3 weeks after birth, when meiosis begins, and increased in amount depending on the maturation of spermatogenesis. The matured sperm, which consists of only post-meiotic cells, is most likely to have only the testis-specific isoform of CaN beta. The brain type isoform of CaN beta was not detected in rat sperm. Immunoblot analysis of testes from different rodent species by a monoclonal antibody Va1 showed that all rodent species examined had their own homologues corresponding to a testis-specific isoform of CaN beta in rats, although they showed distinctively different molecular weights on SDS-PAGE compared to the testis-specific isoform in rats. Each homologue was shown to be specifically expressed in post-meiotic phase of spermatogenesis, as was seen in rats. 相似文献
8.
Effects of 1,1-dimethyl-4-(phenylsulfonyl)semicarbazide (DPSS) on carnation flower longevity 总被引:2,自引:0,他引:2
Naoki Midoh Yuki Saijou Kuniomi Matsumoto Michiaki Iwata 《Plant Growth Regulation》1996,20(3):195-199
The effects of a novel preservative for cut carnation flowers, 1,1-dimethyl-4-(phenylsulfonyl)semicarbazide (DPSS), were investigated. DPSS extended the vase life of cut carnation flowers not only by continuous treatment but pulse treatment as well. This inhibition of senescence by DPSS appeared to depend on that of ethylene production in carnation flowers. DPSS provided no protection from the action of ethylene nor did it inhibit 1-aminocyclopropane-1-carboxylic acid (ACC) synthase. It did inhibit ACC-dependent ethylene production in carnation petal discs, suggesting possible potential for inhibiting ACC oxidase. 相似文献
9.