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Hiroshi KAGAMI Jun YASUDA Takahiro TAGAMI Mitsuru NAITO Yuko MATSUBARA Takashi HARUMI Takamasa NOGUCHI Yasuhiro YAMAMOTO Taikai TAKAHASHI Junichi MATSUYAMA Hiroyuki KOMATSU Tamao ONO 《Animal Science Journal》2002,73(6):453-456
Effect of the strain combination of the donor and recipient on production efficiency of W‐bearing sperm in mixed‐sex chimeric testes was analyzed. The combinations of the donors and recipients were White Leghorn (WL) and Rhode Island Red (RIR), and vice versa. Generated mixed‐sex chimeras that had the male phenotype at sexual maturity were classified into four groups: (1) a female WL donor and a male RIR recipient; (2) a male WL donor and a female RIR recipient; (3) a female RIR donor and a male WL recipient; (4) a male RIR donor and a female WL recipient. The mean number of W‐bearing sperm detected by in situ hybridization among 10 000 sperm observed were 147, 165, 30 and 45 in groups 1, 2, 3 and 4, respectively. The numbers in groups 1 and 2 were both significantly higher than those of groups 3 and 4 (P < 0.05). The combination of a WL donor and a RIR recipient produced W‐bearing sperm more efficiently than the reverse combination. 相似文献
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A new device for monitoring the activity of freely swimming flatfish, Japanese flounder Paralichthys olivaceus 总被引:1,自引:0,他引:1
RYO KAWABE KATSUAKI NASHIMOTO TOMONORI HIRAISHI YASUHIKO NAITO KATSUFUMI SATO 《Fisheries Science》2003,69(1):3-10
ABSTRACT: The tail beat and activity behavior of four captive Japanese flounder Paralichthys olivaceus , were monitored with acceleration data-loggers while the fish swam in an aquarium. Depth, swimming speeds and two-axis acceleration data were collected continuously for approximately 20 h per fish. Simultaneously, the swimming behaviors of the fish were filmed at different angles. Using the specific characteristic of the acceleration profiles, in tandem with other types of data (e.g. speed and depth), four behavioral patterns could be distinguished: (i) 'active' swimming; (ii) burying patterns; (iii) 'inactive' gliding; and (iv) lying on the bottom. Tail beat frequency ranged from 1.65 ± 0.47 to 2.04 ± 0.25 Hz (mean ± SD; n = 4). Using the relationship between tail beat frequency and swimming speed, the 'preferred' swimming speed of the fish was estimated to be between 0.6 and 1.2 body lengths (BL)/s. Additionally, fish rarely swam faster than 1.2 BL/s. This study shows that the acceleration data-loggers represent a useful and reliable system for accurately recording the tail beat of free-ranging fish and estimating flatfish behavior. 相似文献
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Wataru FUJII Asuka ONUMA Shin YOSHIOKA Keisuke NAGASHIMA Koji SUGIURA Kunihiko NAITO 《The Journal of reproduction and development》2015,61(6):589-593
The generation efficiencies of mutation-induced mice when using engineered zinc-finger nucleases (ZFNs) have
been generally 10 to 20% of obtained pups in previous studies. The discovery of high-affinity DNA-binding
modules can contribute to the generation of various kinds of novel artificial chromatin-targeting tools, such
as zinc-finger acetyltransferases, zinc-finger histone kinases and so on, as well as improvement of reported
zinc-finger recombinases and zinc-finger methyltransferases. Here, we report a novel ZFN pair that has a
highly efficient mutation-induction ability in murine zygotes. The ZFN pair induced mutations in all obtained
mice in the target locus, exon 17 of aminopeptidase Q gene, and almost all of the pups had biallelic
mutations. This high efficiency was also shown in the plasmid DNA transfected in a cultured human cell line.
The induced mutations were inherited normally in the next generation. The zinc-finger modules of this ZFN pair
are expected to contribute to the development of novel ZF-attached chromatin-targeting tools. 相似文献
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Mitsuru NAITO 《Animal Science Journal》2003,74(3):157-168
The development of chicken embryo culture techniques, from single‐cell stage to hatching, makes it possible to manipulate developing embryos at any developmental stage. Production of germline chimeric chickens by the transfer of stage X blastodermal cells or primordial germ cells enables the manipulation of germline cells in vitro. Production of transgenic chickens has been attempted by the retroviral vector method, microinjection of DNA into a fertilized ovum at the single‐cell stage, use of chimeric intermediates produced by the transfer of stage X blastodermal cells or primordial germ cells, manipulation of spermatozoa, and in vivo manipulation of gonads. So far, the only non‐viral method that has successfully produced transgenic chickens is microinjection of DNA into a fertilized ovum. Manipulation of primordial germ cells could become an efficient system for producing transgenic chickens by combining it with the highly efficient transfection method or the in vitro culture system for primordial germ cells. Preservation of avian genetic resources has now become possible by cryopreservation of stage X blastodermal cells or primordial germ cells as well as spermatozoa. The development of nuclear transfer techniques for avian species is necessary. 相似文献
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Keiji OKADA Junro KATO Tamako MIYAZAKI Kentaro IKUTA Yoshihisa NAITO Jun YASUDA 《Animal Science Journal》2009,80(1):12-18
Inadequate milk curd formation in the abomasum of newborn calves causes malnutrition and diarrhea. In order to define the factors of inadequate curd formation, we compared the curd forming ability among 9 kinds of milk replacers, bulk milk (raw milk), and skim milk both in vitro and in vivo . When rennet was added, the raw milk and one milk replacer formed firm curds. The rest of the milk replacers and skim milk did not form any curd. When a solution of HCl was added, raw milk, three milk replacers and skim milk formed the curd at pH 4.5, but the other milk replacers did not. When HCl was added following the rennet, raw milk, one milk replacer and skim milk formed the curd. In vivo , raw milk, two milk replacers and skim milk showed good curd formation whereas the other milk replacers showed poor curd formation inside the abomasums of the calves. This study showed that most of the milk replacers sold in Japan could not form the curd with rennet. 相似文献
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Miyuki KITAOKA Shuichi HIRAI Hayato TERAYAMA Munekazu NAITO Ning QU Naoyuki HATAYAMA Hidenobu MIYASO Yoshiharu MATSUNO Masatoshi KOMIYAMA Masahiro ITOH Chisato MORI 《The Journal of reproduction and development》2013,59(5):485-490
Exposure to di-(2-ethylhexyl) phthalate (DEHP) has been reported to induce
spermatogenic disturbance through oxidant stress and affect the immune system as an
adjuvant. However, the effect of DEHP on the testicular immune microenvironment has
not yet been investigated. In the present study, we examined the testicular immune
microenvironment after exposure to doses of DEHP, previously identified as
no-observed-adverse-effect levels. Adult male mice were administered food containing
0%, 0.01% or 0.1% DEHP and then testes were analyzed. The results showed that a
slight but significant spermatogenic disturbance appeared in the 0.1% DEHP group but
not in the 0.01% DEHP group at 8 weeks. It was also demonstrated that lymphocytes and
F4/80- and MHC class II- positive cells were significantly increased with the
elevation of IL-10 and IFN-γ mRNA expressions in the testes of not only the 0.1% DEHP
group but also the 0.01% DEHP group at 8 weeks. Histochemical analyses involving
horseradish peroxidase (HRP) as a tracer showed that a little blood-borne HRP had
infiltrated into the lumen of a few seminiferous tubules beyond the
blood-testis-barrier in both the 0.1% and 0.01% DEHP groups at 8 weeks. This
indicates that a dose of DEHP that has little effects on spermatogenesis can change
the testicular immune microenvironment with functional damage of the blood-testis
barrier. 相似文献
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Ovarian immature oocytes accumulate many dormant maternal mRNAs, which have short poly(A) tails. Cytoplasmic‐polyadenylation‐element binding protein (CPEB) has been reported to play key roles for the elongation of the tails and the translation of these mRNAs in Xenopus oocytes. However, the functions of CPEB in meiotic resumption have not yet been established in mammalian oocytes. The present study examined the roles of porcine CPEB in Cyclin B syntheses and meiotic resumption of porcine oocytes. Porcine CPEB1 (pCPEB1) cDNA was cloned from total RNA of immature oocytes by RT‐PCR. The overexpression of pCPEB1 by mRNA injection into immature oocytes increased Cyclin B expression and the rate of meiotic resumption. Conversely, the inhibition of endogenous CPEB by expression of a dominant‐negative mutant pCPEB1 (AA‐CPEB), which replaced the expected phosphorylation sites with alanines, had the effect of inhibiting Cyclin B synthesis, ribosomal S6 kinase phosphorylation (an indicator of Mos activity), and meiotic resumption. The inhibition of porcine Aurora A by an injection of antisense RNA enhanced the inhibitory effects of AA‐CPEB. These results suggest the involvement of mammalian CPEB1 in Cyclin B syntheses and meiotic resumption in mammalian oocytes. In addition, the phosphorylation sites of pCPEB1 were identified and are suggested to be phosphorylated by porcine Aurora A. 相似文献