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71.
Shotaro Hirase Ayumi Tezuka Atsushi J. Nagano Mana Sato Sho Hosoya Kiyoshi Kikuchi Wataru Iwasaki 《Evolution; international journal of organic evolution》2021,75(1):176-194
Hybridization between divergent lineages generates new allelic combinations. One mechanism that can hinder the formation of hybrid populations is mitonuclear incompatibility, that is, dysfunctional interactions between proteins encoded in the nuclear and mitochondrial genomes (mitogenomes) of diverged lineages. Theoretically, selective pressure due to mitonuclear incompatibility can affect genotypes in a hybrid population in which nuclear genomes and mitogenomes from divergent lineages admix. To directly and thoroughly observe this key process, we de novo sequenced the 747‐Mb genome of the coastal goby, Chaenogobius annularis, and investigated its integrative genomic phylogeographics using RNA‐sequencing, RAD‐sequencing, genome resequencing, whole mitogenome sequencing, amplicon sequencing, and small RNA‐sequencing. Chaenogobius annularis populations have been geographically separated into Pacific Ocean (PO) and Sea of Japan (SJ) lineages by past isolation events around the Japanese archipelago. Despite the divergence history and potential mitonuclear incompatibility between these lineages, the mitogenomes of the PO and SJ lineages have coexisted for generations in a hybrid population on the Sanriku Coast. Our analyses revealed accumulation of nonsynonymous substitutions in the PO‐lineage mitogenomes, including two convergent substitutions, as well as signals of mitochondrial lineage‐specific selection on mitochondria‐related nuclear genes. Finally, our data implied that a microRNA gene was involved in resolving mitonuclear incompatibility. Our integrative genomic phylogeographic approach revealed that mitonuclear incompatibility can affect genome evolution in a natural hybrid population. 相似文献
72.
73.
Motosugi Nanane Nakamura Futoshi Nakajima Souta Takahata Chihiro Kawamura Kazuhiro Morimoto Junko 《Landscape and Ecological Engineering》2021,17(2):95-106
Landscape and Ecological Engineering - There have been many earlier studies of the biodiversity and ecosystem services of abandoned farmlands, but studies of abandoned villages are limited,... 相似文献
74.
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
75.
Lizard beetles (Erotylidae, Languriinae, Languriini) are known as stem borers of plants and contain agricultural pests and endangered species, but their species–host plant associations have been poorly documented. Here we investigated the larval host plants of two species of the genus Tetraphala Strum, T. collaris (Crotch) and Tetraphala sp. occurring in Taiwan. Females of T. collaris excavated living leafstalks and stems of the herbaceous dicot, Sambucus chinensis (Adoxaceae) using their mandibles for oviposition. We observed the eggs and early-instar larvae inside and nearby oviposition holes and late-instar larvae inside stems, suggesting that T. collaris uses living leafstalks and stems of S. chinensis as oviposition substrate and the larvae tunnel into stems with feeding on the tissues. Similarly, females of Tetraphala sp. excavated living leafstalks of the fern, Pteris wallichiana (Pteridaceae) using their mandibles for oviposition. We observed the eggs and early-instar larvae inside and nearby oviposition holes. When reared in laboratory, a larva reached adulthood inside the leafstalk. These results indicated that Tetraphala sp. uses living leafstalks of Pt. wallichiana as oviposition substrate and the larvae complete their development within. This study revealed that the genus Tetraphala contains both fern- and dicot-users during larval period. Further study is needed to clarify the evolutionary process of host plant use of languriines. Additionally, the host plant list of Languriini is provided. 相似文献
76.
Hatakeyama Wataru Lee Cliff Da Silva John Kim David M. Nagai Shigemi Kondo Hisatomo Nagai Masazumi 《International journal of peptide research and therapeutics》2021,27(2):957-965
International Journal of Peptide Research and Therapeutics - A DNA hybridization-based differential peptide display (DPD) was developed for the screening of phage peptide library to find osteogenic... 相似文献
77.
Hiroyuki Morimoto Hirohiko Okamura Kaya Yoshida Seiichiro Kitamura Tatsuji Haneji 《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):327-331
The reversible phosphorylation of proteins mediates cellular signals in eukaryotic cells. RNA interference inhibits the expression of genes and proteins in a sequence-specific manner and provides a tool to study the functions of target molecules. The effect of RNA interference on protein phosphatase isoforms in HEK-293 cells was examined. Protein phosphatase 1 delta (PP1δ) sequence-specific double-stranded RNA (dsRNA) inhibited mRNA and protein expression of the PP18. This RNA interference did not affect the expression of α and γ1 isoforms of PP1. Transfection of antisense RNA specific for PP1δ also suppressed the expression of PP1δ. It was further demonstrated by an in vitro RNA cleavage assay that extracts of HEK-293 cells catalyzed the processing of dsRNA. This cell line had much stronger mRNA expression of Dicer, an RNase III-like enzyme, than did human osteoblastic MG63 cells. The present results show that RNA interference is a useful tool to distinguish between PP1 isoforms. 相似文献
78.
Kouhei Nagai Koichi Morimoto Haruka Ikegami Hajime Kimura Norishige Yotsukura 《Marine biotechnology (New York, N.Y.)》2013,15(4):487-498
Proteomic profiles of the lamina of Ecklonia kurome Okamura, one of the Japanese dominant laminarialean kelps, were investigated by two-dimensional electrophoresis (2-DE) and MALDI-TOF/TOF. Due to the absence of E. kurome DNA or protein databases, homology-based cross-species protein identification was performed using a combination of three database-searching algorithms, Mascot peptide mass fingerprinting, Mascot MS/MS ion search, and mass spectrometry-based BLAST. Proteins were extracted from the lamina by an ethanol/phenol method and subjected to 2-DE (pI 4–7, 10 % polyacrylamide gel). More than 700 spots were detected in the 2-DE gel with CBB, and 93 spots (24 proteins) were successfully identified by MALDI-TOF/TOF and the cross-species database searching. The identified proteins mainly consisted of cytoplasmic carbohydrate metabolic enzymes, chloroplast proteins involved in photosynthesis, and haloperoxidases. Interestingly, vanadium-dependent bromoperoxidases (vBPO), which is thought to be involved in halogen uptake, synthesis of halogenated products, and detoxification of reactive oxygen species, were separated into at least 23 different spots. By comparing mass spectra, amino acid sequences predicted from tandem mass spectra and haloperoxidase activities of the vBPOs, we found that (1) at least two types of vBPOs were expressed in the lamina of E. kurome and (2) two pro-vBPOs might be activated by specific cleavage at N- and C-terminal regions. 相似文献
79.
The emergence of the occipital alpha rhythm on brain electroencephalogram (EEG) is associated with brain activity in the cerebral neocortex and deep brain structures. To further understand the mechanisms of alpha rhythm power fluctuation, we performed simultaneous EEGs and functional magnetic resonance imaging recordings in human subjects during a resting state and explored the dynamic relationship between alpha power fluctuation and blood oxygenation level-dependent (BOLD) signals of the brain. Based on the frequency characteristics of the alpha power time series (APTS) during 20-minute EEG recordings, we divided the APTS into two components: fast fluctuation (0.04–0.167 Hz) and slow fluctuation (0–0.04 Hz). Analysis of the correlation between the MRI signal and each component revealed that the slow fluctuation component of alpha power was positively correlated with BOLD signal changes in the brain stem and the medial part of the thalamus and anterior cingulate cortex, while the fast fluctuation component was correlated with the lateral part of the thalamus and the anterior cingulate cortex, but not the brain stem. In summary, these data suggest that different subcortical structures contribute to slow and fast modulations of alpha spectra on brain EEG. 相似文献
80.
Soluble oligomeric amyloid-β (Aβ) has been suggested to impair synaptic and neuronal function, leading to neurodegeneration that is clinically observed as the memory and cognitive dysfunction characteristic of Alzheimer disease, while the precise mechanism(s) whereby oligomeric Aβ causes neurotoxicity remains unknown. Recently, the cellular prion protein (PrPC) was reported to be an essential co-factor in mediating the neurotoxic effect of oligomeric Aβ. Our recent study showed that Prnp−/− mice are resistant to the neurotoxic effect of oligomeric Aβ in vivo and in vitro. Furthermore, application of an anti-PrPC antibody or PrPC peptide was able to block oligomeric Aβ-induced neurotoxicity. These findings demonstrate that PrPC may be involved in neuropathologic conditions other than conventional prion diseases, i.e., Creutzfeldt-Jakob disease. 相似文献