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131.
Yui?Kono Hiroko?SasakiEmail author Yukari?Kurihara Amane?Fujiwara Jun?Yamamoto Yasunori?Sakurai 《Polar Biology》2016,39(6):1039-1048
Polar cod, Boreogadus saida, is a key species in the Arctic Ocean ecosystem. We examined the distribution pattern of B. saida and other fish larvae in relation to oceanographic parameters, including sea surface temperature and salinity (SST and SSS), the mode of temperature and salinity within the water column (F temp and F sal), and the temporal duration between the date of sea ice retreat and the date of field surveys (dSRT) in the northern Bering Sea and Chukchi Sea during the summers of 2008 and 2013. Sampling was conducted onboard the T/S Oshoro-Maru using a bongo net for 2 years. At sampling stations, the temperature and salinity were measured using conductivity-temperature-depth profiler casts. We calculated dSRT from satellite derived polar gridded sea ice concentration data. A total of 1186 individuals comprising 7 families and 16 species were collected, with B. saida (35 %) and Ammodytes hexapterus (27 %) dominating the catch in number. Based on the species composition (cluster analysis), the sampling stations were divided into four groups. Pleuronectidae dominated group A, which was characterized by relatively high temperature (SST and F temp), while B. saida dominated group B, characterized by low temperatures. A. hexapterus dominated group C and D, which had similar temperatures and salinities, but group C had a shorter dSRT than group D. The latter was also differentiated by the presence of Lumpenus sp. B. saida, which were most abundant in regions where temperatures ranged from ?2 to 0.5 °C. These results, the geographical variation of group B sampling stations, suggest there are two separate spawning areas characterized by similar fish communities and related to consistently cold bottom temperatures. Moreover, stations with a higher abundance of smaller sized larval B. saida were characterized by a short dSRT, whereas stations with a lower abundance and a larger size were characterized by a long dSRT. 相似文献
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K Miura S Ohgiya T Hoshino N Nemoto M Odaira K Nitta S Tsuda 《Journal of biochemistry》1999,126(2):387-394
RD3, a new antifreeze protein (AFP) extracted from antarctic eel pout is a single polypeptide divided into homologous N-terminal (residues Asn(1)-Glu(64)) and C-terminal (residues Ser(74)-Glu(134)) domains, each of which has a high sequence identity with Type III AFP. A 9-residue linker (-D(65)GTTSPGLK(73)-) connects these two domains in tandem and is thought to play a significant role in defining the nature of the intact molecule. The present paper shows for the first time the solution structure and preliminary (15)N-NMR backbone dynamics data of the N-domain plus the linker of recombinant RD3 protein (RD3-Nl: residues 1-73) by employing homo- and heteronuclear multidimensional NMR spectroscopy. Forty converged structures of RD3-Nl were successfully calculated by using a total of 958 NMR-derived structural restraints. It was found that the N-domain of RD3-Nl has a globular form comprising six beta-strands, three type III turns, and several loops, which stabilize a flat, ice-binding site formed on one side of this domain. Further, the linker portion appears to have a definitive structure, which is independent of the globular N-domain. This definitive linker is roughly divided into two short strands, -D(65)GTTSP(70)- and -G(71)LK(73)-, which are bent around -T(67)TSPG(71)- at an angle of approximately 60 degrees. This bending motif of the linker may function to orient the two ice-binding sites of the N- and C-domains of RD3 in the same direction, leading to their simultaneous interactions with the ice crystal surface. 相似文献
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136.
Alessandra Bartolozzi Asitha Abeywardane Todd Bosanac John A. Broadwater Zhidong Chen J. Matthew Hutzler John D. Huber Peter Nemoto Alan Olague Doris Riether Tom Simpson Hidenori Takahashi Lifen Wu Yunlong Zhang Renee M. Zindell 《Bioorganic & medicinal chemistry letters》2017,27(20):4652-4659
Structure activity relationship (SAR) investigation of an oxadiazole based series led to the discovery of several potent FLAP inhibitors. Lead optimization focused on achieving functional activity while improving physiochemical properties and reducing hERG inhibition. Several compounds with favorable in vitro and in vivo properties were identified that were suitable for advanced profiling. 相似文献
137.
Umehara K Nemoto K Kimijima K Matsushita A Terada E Monthakantirat O De-Eknamkul W Miyase T Warashina T Degawa M Noguchi H 《Phytochemistry》2008,69(2):546-552
From the heartwood of Dalbergia parviflora, five compounds, dalparvin A (1), B (2), C (3), dalparvinol C (4), and neokhriol A (5), along with 11 known compounds, kenusanone G (6), cajanin (7), sophorol (8), alpinetin (9), hesperetin (10), 3'-O-methylorobol, odoratin, (2R)(3R)-2,3-trans 7-hydroxy-5-methoxydihydroflavonol, (6aR, 11aR)-3,8-dihydroxy-9-methoxypterocarpan, (6aR, 11aR)- vesticarpan, and methyl-3,4-dihydroxy-2-methoxybenzoate were isolated and characterized. Isolates were evaluated for their cell proliferation stimulatory activity against MCF-7, T-47D, and BT20 human breast cancer cell lines. Along with 7-10, two compounds 2 and 3 stimulated not only MCF-7, but also T-47D human breast cancer cell proliferation. Compound 6 had activity only against MCF-7 cells, and the activity of 7 was more than equivalent to that of daidzein. On the other hand, none of the isolates had any significant effects on BT20 cell proliferation, and these results indicated that the stimulative activity of these compounds was not general to any cell proliferations. Furthermore, these compounds were tested in the estrogen-responsive transient luciferase reporter assay. 相似文献
138.
cDNA display: a novel screening method for functional disulfide-rich peptides by solid-phase synthesis and stabilization of mRNA–protein fusions
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139.
Nemoto K Hara M Goto S Kasai K Seki H Suzuki M Oka A Muranaka T Mano Y 《Journal of plant physiology》2009,166(7):729-738
Tobacco (Nicotiana tabacum) Bright Yellow-2 (BY-2) cells are rapidly proliferating meristematic cells that require auxin for culture in vitro. We have established several transgenic BY-2 cell lines that carry the T-DNA of Agrobacterium rhizogenes 15834, which harbors an agropine-type root-inducing (Ri) plasmid. Two of these lines, BYHR-3 and BYHR-7, were used to test the role of auxin in the proliferation of plant cells. The lines grew rapidly in Linsmaier-Skoog (LS) medium lacking auxin and other phytohormones. The TR-DNA, containing the aux1 (tryptophan monooxygenase) and aux2 (indoleacetamide hydrolase) genes, was present in the genomes of both transgenic lines, whereas the TL-DNA, containing the rolA, B, C and D genes, was present in the genome of BYHR-7 but not BYHR-3. Since the introduction of the rolABCD genes alone did not affect the auxin requirement of BY-2 cells, the aux1 and aux2 genes, but not the rolABCD genes, appear to be relevant to the auxin autotrophy of these transgenic lines. Furthermore, the overexpression of aux1 allowed BY-2 cells to grow rapidly in the absence of auxin, suggesting the existence in plant cells of an unidentified gene whose product is functionally equivalent or similar to that of aux2 of the Ri plasmid. 相似文献
140.
During early pregnancy in the rat, focal adhesions disassemble in uterine luminal epithelial cells at the time of implantation
to facilitate their removal so that the implanting blastocyst can invade into the underlying endometrial decidual cells. This
study investigated the effect of ovarian hormones on the distribution and protein expression of two focal adhesion proteins,
talin and paxillin, in rat uterine luminal and glandular epithelial cells under various hormone regimes. Talin and paxillin
showed a major distributional change between different hormone regimes. Talin and paxillin were highly concentrated along
the basal cell surface of uterine luminal epithelial cells in response to oestrogen treatment. However, this prominent staining
of talin and paxillin was absent and also a corresponding reduction of paxillin expression was demonstrated in response to
progesterone alone or progesterone in combination with oestrogen, which is also observed at the time of implantation. In contrast,
the distribution of talin and paxillin in uterine glandular epithelial cells was localised on the basal cell surface and remained
unchanged in all hormone regimes. Thus, not all focal adhesions are hormonally dependent in the rat uterus; however, the dynamics
of focal adhesion in uterine luminal epithelial cells is tightly regulated by ovarian hormones. In particular, focal adhesion
disassembly in uterine luminal epithelial cells, a key component to establish successful implantation, is predominantly under
the influence of progesterone. 相似文献