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91.
Telmatochromis temporalis is a biparental substrate breeding cichlid that mates in size-assortative monogamy at the southern end of Lake Tanganyika.
In this population, at least a few months before the rainy season, large males (90–110 mm TL) did not pair. However, they
maintained large territories that were defended against conspecific large males and that contained several pairing small males
(50–80 mm). Large males occasionally visited the nests of the small pairs in their territories, and selectively took over
the nests by attacking the owner male. During the takeover, the large males courted the small females in the nests and might
have ejaculated sperm. After the large males left the nests, the small owner males conducted paternal care at the nests. These
behaviour patterns of large males are similar to piracy mating reported in other polygamous fish species. The piracy mating
of large maleT. temporalis seems to be an alternative tactic when large females are not available. 相似文献
92.
93.
Alfredo Attisano Nozomu J Sato Keita D Tanaka Yuji Okahisa Keisuke Ueda Roman Gula Jrn Theuerkauf 《动物学报(英文版)》2021,67(6):653
Nestling rejection is a rare type of host defense against brood parasitism compared with egg rejection. Theoretically, host defenses at both egg and nestling stages could be based on similar underlying discrimination mechanisms but, due to the rarity of nestling rejector hosts, few studies have actually tested this hypothesis. We investigated egg and nestling discrimination by the fan-tailed gerygone Gerygone flavolateralis, a host that seemingly accepts nonmimetic eggs of its parasite, the shining bronze-cuckoo Chalcites lucidus, but ejects mimetic parasite nestlings. We introduced artificial eggs or nestlings and foreign gerygone nestlings in gerygone nests and compared begging calls of parasite and host nestlings. We found that the gerygone ejected artificial eggs only if their size was smaller than the parasite or host eggs. Ejection of artificial nestlings did not depend on whether their color matched that of the brood. The frequency of ejection increased during the course of the breeding season mirroring the increase in ejection frequency of parasite nestlings by the host. Cross-fostered gerygone nestlings were frequently ejected when lacking natal down and when introduced in the nest before hatching of the foster brood, but only occasionally when they did not match the color of the foster brood. Begging calls differed significantly between parasite and host nestlings throughout the nestling period. Our results suggest that the fan-tailed gerygone accepts eggs within the size range of gerygone and cuckoo eggs and that nestling discrimination is based on auditory and visual cues other than skin color. This highlights the importance of using a combined approach to study discrimination mechanisms of hosts. 相似文献
94.
Biochemical characterization and structural insight into aliphatic β‐amino acid adenylation enzymes IdnL1 and CmiS6
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Jolanta Cieślak Akimasa Miyanaga Ryoma Takaku Makoto Takaishi Keita Amagai Fumitaka Kudo Tadashi Eguchi 《Proteins》2017,85(7):1238-1247
Macrolactam antibiotics such as incednine and cremimycin possess an aliphatic β‐amino acid as a starter unit of their polyketide chain. In the biosynthesis of incednine and cremimycin, unique stand‐alone adenylation enzymes IdnL1 and CmiS6 select and activate the proper aliphatic β‐amino acid as a starter unit. In this study, we describe the enzymatic characterization and the structural basis of substrate specificity of IdnL1 and CmiS6. Functional analysis revealed that IdnL1 and CmiS6 recognize 3‐aminobutanoic acid and 3‐aminononanoic acid, respectively. We solved the X‐ray crystal structures of IdnL1 and CmiS6 to understand the recognition mechanism of these aliphatic β‐amino acids. These structures revealed that IdnL1 and CmiS6 share a common recognition motif that interacts with the β‐amino group of the substrates. However, the hydrophobic side‐chains of the substrates are accommodated differently in the two enzymes. IdnL1 has a bulky Leu220 located close to the terminal methyl group of 3‐aminobutanoate of the trapped acyl‐adenylate intermediate to construct a shallow substrate‐binding pocket. In contrast, CmiS6 possesses Gly220 at the corresponding position to accommodate 3‐aminononanoic acid. This structural observation was supported by a mutational study. Thus, the size of amino acid residue at the 220 position is critical for the selection of an aliphatic β‐amino acid substrate in these adenylation enzymes. Proteins 2017; 85:1238–1247. © 2017 Wiley Periodicals, Inc. 相似文献
95.
Yuki Ohmuro-Matsuyama Keita Mori Hirotsugu Hamada Hiroshi Ueda Hideki Yamaji 《Cytotechnology》2017,69(3):469-475
Monoclonal antibodies and antibody fragments are used for diverse diagnostic and therapeutic applications. We have investigated the secretory production of Fab fragments from insect cells cotransfected with plasmid vectors carrying heavy- and light-chain genes. In the present study, to promote the formation of the disulfide bond between the heavy and light chains, some positively charged amino acid residues were introduced near the cysteine residue for the disulfide bond at the C-terminus of CL, while some negatively charged amino acid residues were added near the cysteine residue for the disulfide bond at the C-terminus of CH1. This electrostatic steering led to an increase in Fab secretions from insect cells. 相似文献
96.
Identification and characterization of a brilliant yellow pigment produced by Bordetella pertussis
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Keita Odanaka Masato Iwatsuki Tomomitsu Satho Mineo Watanabe 《Microbiology and immunology》2017,61(11):490-496
97.
Tokusei Tanahashi Keisuke Kawai Keita Tatsushima Chihiro Saeki Kunie Wakabayashi Naho Tamura Tetsuya Ando Toshio Ishikawa 《BioPsychoSocial medicine》2017,11(1):22
Background
We examined how purging behaviors relate to subjective sleep quality and sleep patterns and how symptoms of disordered eating behaviors relate to global sleep quality in female patients with anorexia nervosa (AN).Methods
Participants were new consecutive female inpatients with a primary diagnosis of AN admitted to the Department of Psychosomatic Medicine at Kohnodai Hospital between June 26 and December 25, 2015. We recorded patients’ habitual eating behaviors, laxative overuse, or uretic misuse, and administered the Japanese versions of the Pittsburgh Sleep Quality Index (PSQI-J) and Center for Epidemiologic Studies Depression Scale. Raw PSQI-J data were used to determine sleep patterns (sleep-onset time, wake-up time, and sleep duration). To examine how purging behaviors related to sleep quality, we compared variables between AN restricting type (ANr) and AN binge-eating/purging type (ANbp). Spearman’s rank correlation analysis was used to examine which potential factors influence global PSQI-J score.Results
Participants were 20 patients, of whom 12 had ANbp. Two ANr patients (25%) had global PSQI-J scores greater than 5, compared to 9 ANbp patients (75%; P < 0.05). Circadian rhythm disruption and abnormal sleep duration were significantly greater in ANbp patients than in ANr patients (P < 0.05). Global PSQI-J was significantly correlated with a diagnosis of ANbp (ρ = 0.525; P < 0.05), vomiting (ρ = 0.561; P < 0.05), and duration of illness (ρ = 0.536; P < 0.05).Conclusions
ANbp patients had worse global sleep quality and greater disrupted sleep than did ANr patients. This suggests that treatments focusing on sleep would be useful, especially for ANbp patients. Furthermore, vomiting and duration of illness should be considered essential factors related to impaired global sleep quality.Trial registration
Not applicable.98.
Bactericidal Actions of a Silver Ion Solution on Escherichia coli, Studied by Energy-Filtering Transmission Electron Microscopy and Proteomic Analysis 总被引:1,自引:0,他引:1
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Bactericidal actions of the silver ion on Escherichia coli as a model microorganism were studied using energy-filtering transmission electron microscopy (EFTEM), two-dimensional electrophoresis (2-DE), and matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS). EFTEM observations demonstrated that the silver ion readily infiltrates the interior of E. coli, contrary to the early hypothesis that it resides initially in the cell membrane area. Furthermore, 2-DE and MALDI-TOF MS indicated that the expression of a ribosomal subunit protein as well as that of some other enzymes and proteins is affected by the silver ion. The present results demonstrate for the first time that one of the major bactericidal functions of the silver ion is its interaction with the ribosome and the ensuing inhibition in expression of the enzymes and proteins essential to ATP production. 相似文献
99.
Fujioka T Kaneko F Kazama T Suwabe K Suzuki G Makino A Mae T Endo M Kawagishi-Kobayashi M Watanabe M 《Genes & genetic systems》2008,83(3):281-284
Small RNAs including microRNA (miRNA) and small interfering RNA (siRNA) are known as repressors of gene expression. There are many plant proteins involved in small RNA-mediated gene silencing, such as Dicer ribonucleases and RNA-dependent RNA polymerases. However, most of these proteins have been reported to be absent in the late developmental stage of the plant male gamete, pollen. In order to clarify the existence of the small RNAs during maturation of pollen, we cloned and sequenced small RNAs from rice anthers including tricellular pollen. From fifty six candidates of small RNAs, we identified two known miRNAs (miR166 and miR167), eight potential miRNAs, and ten putative heterochromatic siRNAs (hc-siRNAs). RNA gel blot analyses clearly showed that miR166 and miR167 were accumulated in the uninuclear pollen stage of anther development and remained until the tricellular pollen stage. Our cloning and RNA gel blot analyses of small RNAs led us to propose a possible function of small RNA-mediated gene regulation for the development of male gametes in rice. 相似文献
100.
The freezing behavior of dormant buds in larch, especially at the cellular level, was examined by a Cryo-SEM. The dormant buds exhibited typical extraorgan freezing. Extracellular ice crystals accumulated only in basal areas of scales and beneath crown tissues, areas in which only these living cells had thick walls unlike other tissue cells. By slow cooling (5 °C/day) of dormant buds to −50 °C, all living cells in bud tissues exhibited distinct shrinkage without intracellular ice formation detectable by Cryo-SEM. However, the recrystallization experiment of these slowly cooled tissue cells, which was done by further freezing of slowly cooled buds with LN and then rewarming to −20 °C, confirmed that some of the cells in the leaf primordia, shoot primordia and apical meristem, areas in which cells had thin walls and in which no extracellular ice accumulated, lost freezable water with slow cooling to −30 °C, indicating ability of these cells to adapt by extracellular freezing, whereas other cells in these tissues retained freezable water with slow cooling even to −50 °C, indicating adaptation of these cells by deep supercooling. On the other hand, all cells in crown tissues and in basal areas of scales, areas in which cells had thick walls and in which large masses of ice accumulated, had the ability to adapt by extracellular freezing. It is thought that the presence of two types of cells exhibiting different freezing adaptation abilities within a bud tissue is quite unique and may reflect sophisticated freezing adaptation mechanisms in dormant buds. 相似文献