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21.
Kishi H Ohshima K Itoh M Tsukada J Arai KY Nakano S Watanabe G Taya K 《Zoological science》2002,19(2):225-232
In the present study, changes in localization of each inhibin subunit in the ovary were investigated during the estrous cycle of the golden hamster. The effect of LH surge on changes in localization in inhibin alpha subunit in the ovary was also investigated. Inhibin alpha subunit was localized in granulosa cells of various stages of follicles throughout the estrous cycle. Inhibin alpha subunit was also present in numerous interstitial cells on days 1 and 2 (day 1 = day of ovulation), but the number of positive interstitial cells was fewer on days 3 and almost disappeared on day 4 of the estrous cycle. Newly formed luteal cells were also positive for inhibin alpha subunit on days 1 and 2. On the other hand, positive reactions for inhibin beta A and beta B subunits were only present in the granulosa cells of healthy antral follicles. However, a positive reaction for inhibin beta B subunit in peripheral mural granulosa cells disappeared on days 3 and 4 of the estrous cycle. Treatment with LHRH-AS at 1100 h on day 4 completely blocked the luteinizing hormone (LH) surge and ovulation, although relatively high concentrations of plasma follicle-stimulating hormone (FSH) were maintained throughout the experiment. There were few positive reactions for inhibin alpha subunit in theca and interstitial cells 24 hr after LHRH-AS injection. The effect of LHRH-AS treatment was blocked by a single injection of 10 IU human chorionic gonadotropin. These results suggest that the major source of dimeric inhibin in the cyclic hamster was granulosa cells of healthy antral follicles. Different distribution pattern of inhibin beta A from beta B subunits in large antral follicles on days 3 and 4 of the estrous cycle suggests different secretion patterns of inhibin A from B on these days. Furthermore, the LH surge may be an important factor to induce production of inhibin alpha subunit in interstitial cells of the cyclic hamster. 相似文献
22.
Akiko Sogo Hiroaki Setoguchi Junko Noguchi Tanguy Jaffré Hiroshi Tobe 《Journal of plant research》2001,114(4):459-464
rbcL (1310 bp) and matK (1014 bp), using 15 species representing the family. The study included analyses of Ticodendron (Ticodendraceae) and three species of Betulaceae as close relatives, and one species each of Juglandaceae and Myricaceae
as outgroups. Analyses based on matK gene sequences, which provided a much better resolution than the analyses based on rbcL gene sequences alone, resulted in a single most parsimonious tree whose topology is almost identical with the strict consensus
tree generated by the combined data set of rbcL and matK gene sequences. Results showed that Casuarinaceae are monophyletic, comprising four distinct genera, Allocasuarina, Casuarina, Ceuthostoma and Gymnostoma, which were not recognized until recently. Within the family, Gymnostoma is positioned at the most basal position and sister to the remainder. Within the remainder Ceuthostoma is sister to the Allocasuarina-Casuarina clade. Morphologically the basalmost position of Gymnostoma is supported by plesiomorphies such as exposed stomata in the shallow longitudinal furrows of the branchlets, a basic chromosome
number x=8 and the gynoecium composed of two fertile, biovulate carpels. The three other genera, Allocasuarina, Casuarina, and Ceuthostoma, have invisible stomata in the deep longitudinal furrows of the branchlets, a higher basic chromosome number x=9 or 10–14 (unknown in Ceuthostoma), the gynoecium composed of one fertile and one sterile carpel with a single ovule (unknown in Ceuthostoma). The diversity of infructescence morphology found in the latter three genera suggests that they may have evolved in close
association with the elaboration of fruit dispersal mechanisms.
Received 14 September 2001/ Accepted in revised form 12 October 2001 相似文献
23.
Sakiyama Tomoki Morimoto Junko Matsubayashi Jun Furukawa Yasuto Kondo Mami Tsuruga Hifumi Mano Tsutomu Nakamura Futoshi 《Landscape and Ecological Engineering》2021,17(3):351-362
Landscape and Ecological Engineering - Investigating factors underlying human-wildlife conflicts in agricultural landscapes is important for both preventing crop damage and wildlife conservation.... 相似文献
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MicroRNA (miR)-17-92a expression plays a crucial role in lymphocyte ontogeny. We therefore set out to determine miR-92a expression levels in peripheral blood lymphocytes from healthy subjects to ascertain any association between these levels and ageing. We found a positive correlation between the miR-92a expression level and the percentages of RO-CD8+CD27+ (P = 0.0046) and CD3+CD8+CD62L+ (P = 0.0011). This suggests that the majority of miR-92a of CD8+ T cells is derived from naïve cells, and the miR-92a expression level in CD8+ T cells declines progressively with age. These results indicate that the age-related attrition of naïve T cells is linked to a reduction of miR-92a in human T -lymphocytes. Therefore, we should careful attention when evaluating human miRNA levels in T lymphocytes to use normal control values. 相似文献
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Jun Qian Shinji Ito Junko Satoh Hongmin Geng Keisuke Tanaka Shunji Hattori 《Bioscience, biotechnology, and biochemistry》2017,81(3):514-522
Bovine type I collagen consists of two α1 and one α2 chains, containing the internal triple helical regions and the N- and C-terminal telopeptides. In industries, it is frequently digested with porcine pepsin to produce a triple helical collagen without the telopeptides. However, the digestion mechanism is not precisely understood. Here, we performed a mass spectrometric analysis of the pepsin digest of the N-terminal telopeptide pQLSYGYDEKSTGISVP (1–16) in the α1 chain. When purified collagen was digested, pQLSYGY (1–6) and pQLSYGYDEKSTG (1–12) were identified, while DEKSTG (7–12) was not. When the N-terminal telopeptide mimetic synthetic peptide pQLSK(MOCAc)GYDEKSTGISK(Dnp)P-NH2 was digested, pQLSK(MOCAc)GYDEKSTG (1–12) and ISK(Dnp)P-NH2 (13?16) were readily identified, pQLSK(MOCAc)GY (1?6) and DEKSTGISK(Dnp)P-NH2 (7?16) were weakly detected, and DEKSTG (7–12) was hardly identified. These results suggest that pepsin preferentially cleaves Tyr6–Asp7 and less preferentially Gly12–Ile13. They also suggest that the former cleavage requires native collagen structure, while the latter cleavage does not. 相似文献
28.
Analysis of bisulfite sequencing data usually requires two tasks: to call methylated cytosines (mCs) in a sample, and to detect differentially methylated regions (DMRs) between paired samples. Although numerous tools have been proposed for mC calling, methods for DMR detection have been largely limited. Here, we present Bisulfighter, a new software package for detecting mCs and DMRs from bisulfite sequencing data. Bisulfighter combines the LAST alignment tool for mC calling, and a novel framework for DMR detection based on hidden Markov models (HMMs). Unlike previous attempts that depend on empirical parameters, Bisulfighter can use the expectation-maximization algorithm for HMMs to adjust parameters for each data set. We conduct extensive experiments in which accuracy of mC calling and DMR detection is evaluated on simulated data with various mC contexts, read qualities, sequencing depths and DMR lengths, as well as on real data from a wide range of biological processes. We demonstrate that Bisulfighter consistently achieves better accuracy than other published tools, providing greater sensitivity for mCs with fewer false positives, more precise estimates of mC levels, more exact locations of DMRs and better agreement of DMRs with gene expression and DNase I hypersensitivity. The source code is available at http://epigenome.cbrc.jp/bisulfighter. 相似文献
29.
Masayuki Ikeda Shigeru Suzuki Masahiro Kishio Moritoshi Hirono Takashi Sugiyama Junko Matsuura Teppei Suzuki Takayuki Sota Charles N. Allen Shiro Konishi Tohru Yoshioka 《Biophysical journal》2004,86(1):565-575
Abundant evidences demonstrate that deuterium oxide (D2O) modulates various secretory activities, but specific mechanisms remain unclear. Using AtT20 cells, we examined effects of D2O on physiological processes underlying β-endorphin release. Immunofluorescent confocal microscopy demonstrated that 90% D2O buffer increased the amount of actin filament in cell somas and decreased it in cell processes, whereas β-tubulin was not affected. Ca2+ imaging demonstrated that high-K+-induced Ca2+ influx was not affected during D2O treatment, but was completely inhibited upon D2O washout. The H2O/D2O replacement in internal solutions of patch electrodes reduced Ca2+ currents evoked by depolarizing voltage steps, whereas additional extracellular H2O/D2O replacement recovered the currents, suggesting that D2O gradient across plasma membrane is critical for Ca2+ channel kinetics. Radioimmunoassay of high-K+-induced β-endorphin release demonstrated an increase during D2O treatment and a decrease upon D2O washout. These results demonstrate that the H2O-to-D2O-induced increase in β-endorphin release corresponded with the redistribution of actin, and the D2O-to-H2O-induced decrease in β-endorphin release corresponded with the inhibition of voltage-sensitive Ca2+ channels. The computer modeling suggests that the differences in the zero-point vibrational energy between protonated and deuterated amino acids produce an asymmetric distribution of these amino acids upon D2O washout and this causes the dysfunction of Ca2+ channels. 相似文献
30.