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51.
Yeast cells exhibit sustained ultradian oscillations of energy metabolism in coupling with cell cycle and stress resistance oscillations in continuous culture. We have reported that the rhythmic expression of Gts1p is important for the maintenance of ultradian rhythms. Structurally, Gts1p contains sequence motifs similar to N-degron and the ubiquitin association domain, raising the possibility that the Gts1p level is regulated by degradation via ubiquitination. When the lysine residue at the putative ubiquitination site of the N-degron was substituted with arginine, both the protein level and half-life of mutant Gts1p increased. During continuous culture, the protein level of the mutant Gts1p was elevated and did not fluctuate, leading to the disappearance of metabolic oscillation within a day. Furthermore, using three Gts1ps containing mutations in the ubiquitin association domain, we showed that the lower the binding activity of the mutant Gts1ps for polyubiquitin in vitro, the higher the protein level in vivo. Expression of the mutant Gts1ps in the continuous culture resulted in an increase in Gts1p and early loss of the oscillation. Therefore, Gts1p is degraded through conjugation with ubiquitin, and the UBA domain promoted the degradation of ubiquitinated Gts1p, causing a fluctuation in protein level, which is required for the maintenance of metabolic oscillations. 相似文献
52.
Nobuhiro Suzuki Kazuhiro Umezawa Toru Yabe Hisayuki Murai 《Ichthyological Research》1989,36(3):318-326
The development of the eggs and larvae and minute tubercles on the skin surface ofParacheilognathus himantegus larvae were observed. The egg began to hatch approximately 68 hours after insemination and the larvae reached the free-swimming stage 23 days after hatching at water temperature of 22±1°C. The larval development and minute tubercles on the skin surface of this species were similar to those ofAcheilognathus lanceolata, A. limbata, A. signifer andTanakia tanago. However, the shape of the ripe eggs ofP. himantegus differed from those of the four species. As regards the shape of eggs, there was a common characteristic amongP. himantegus, Rhodeus uyekii andA. limbata from Korea. As regards larval development,P. himantegus had two characters also found inRhodeus. These facts seem to suggest thatP. himantegus is closely related toA. lanceolata, A. limbata, A. signifer andT. tanago but is more specialized than these four species, except forA. limbata from Korea. 相似文献
53.
Atsuko Takagi Yasuyuki Ikeda Kunihisa Kobayashi Kazuhiro Kobayashi Yoshihiko Ikeda Junji Kozawa Hideyuki Miyauchi Ming Li Chikako Hashimoto Yasuhiro Hara Satoshi Yamaguchi Akira Suzuki Tatsushi Toda Hironori Nagasaka Ken-ichi Hirano 《Biochemical and biophysical research communications》2018,495(1):646-651
Triglyceride deposit cardiomyovasculopathy (TGCV) is a rare and newly identified disease among patients requiring cardiac transplantation. TGCV is characterized by cardiomyocyte steatosis and triglyceride (TG)-deposit atherosclerosis, resulting from the abnormal intracellular metabolism of TG. TGCV is classified into primary and idiopathic types. Primary TGCV carries ultra-rare genetic mutations in the adipose triglyceride lipase (ATGL), a rate-liming enzyme that hydrolyzes intracellular TG in adipose and non-adipose tissues. Idiopathic TGCV, first identified among autopsied individuals with diabetes mellitus (DM) with severe heart diseases, shows no ATGL mutations and its causes and underlying mechanisms are still unknown. TGCV is difficult to diagnose in daily clinics, thereby demanding feasible diagnostic procedures. We aimed to develop an assay to measure ATGL activity using peripheral leucocytes. Human his6-ATGL was expressed in COS1 cells, purified to homogeneity, and used to raise a polyclonal antibody neutralizing TG-hydrolyzing activity of ATGL. We developed a selective immunoinactivation assay (SIIA) for the quantitation of ATGL activity in cell lysates of leucocytes by the antibody neutralizing ATGL activities. ATGL activity was measured in 13 idiopathic TGCV patients, with two patients with primary TGCV as the negative control. Healthy (non-DM) and DM controls without heart diseases were also subjected. The developed SIIA assay revealed significant reduction in ATGL activity in leucocytes from patients with idiopathic TGCV who did not carry ATGL mutations as compared with non-DM and DM controls. Thus, ATGL in leucocytes may be an important biomarker for the diagnosis of TGCV and our assay may provide insights into pathophysiology and elucidate the underlying mechanism of TGCV and related disorders. 相似文献
54.
Ohyama K Shiokawa A Ito K Masuyama R Ichibangase T Kishikawa N Imai K Kuroda N 《Biochemical and biophysical research communications》2012,420(1):210-215
Nonsteroidal anti-inflammatory drugs (NSAIDs) are valuable agents; however, their use has been limited by their association with mucosal damage in the upper gastrointestinal tract. NSAIDs inhibit cyclooxygenase and consequently block the synthesis of prostaglandins, which have cytoprotective effects in gastric mucosa; these effects on prostaglandins have been thought to be major cause of NSAID-induced ulceration. However, studies indicate that additional NSAID-related mechanisms are involved in formation of gastric lesions. Here, we used a toxicoproteomic approach to understand cellular processes that are affected by NSAIDs in mouse stomach tissue during ulcer formation. We used fluorogenic derivatization-liquid chromatography-tandem mass spectrometry (FD-LC-MS/MS)-which consists of fluorogenic derivatization, separation and fluorescence detection by LC, and identification by LC-tandem mass spectrometry-in this proteomic analysis of pyrolic stomach from control and diclofenac (Dic)-treated mice. FD-LC-MS/MS results were highly sensitive; 10 differentially expressed proteins were identified, and all 10 were more highly expressed in Dic-treated mice than in control mice. Specifically, expression levels of 78 kDa glucose-regulated protein (GRP78), heat shock protein beta-1 (HSP27), and gastrin were more than 3-fold higher in Dic-treated mice than in control mice. This study represents a first step to ascertain the precise actors of early NSAID-induced ulceration. 相似文献
55.
M Shinada F Narumi Y Osada K Matsumoto T Yoshida K Higuchi T Kawasaki H Tanaka M Satoh 《Bioorganic & medicinal chemistry》2012,20(16):4901-4914
Phenserine is a potentially attractive drug for Alzheimer's disease. In order to further expand SAR study for inhibitions of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), the methyl group at the 3a-position of phenserine was replaced with an alkyl or alkenyl group, and its phenylcarbamoyl moiety was substituted at the o- or p-position. The synthetic methodology for these phenserine analogues includes the efficient cascade reactions for introduction of the 3a-substituent and assembly of the quaternary carbon center followed by reductive cyclization to the key pyrroloindoline structure. The bulkiness of the substituent at 3a-position of phenserine derivatives tends to reduce the inhibitory effect on AChE activity in the following order: methyl>ethyl>vinyl>propyl≈allyl>reverse-prenyl groups. Among the series synthesized, the 3a-ethyl derivative demonstrated the highest AChE selectivity. In construct, the 3a-reverse-prenyl derivative indicated modest BuChE selectivity. 相似文献
56.
Kazuyuki Nakamura Hirofumi Kodera Tenpei Akita Masaaki Shiina Mitsuhiro Kato Hideki Hoshino Hiroshi Terashima Hitoshi Osaka Shinichi Nakamura Jun Tohyama Tatsuro Kumada Tomonori Furukawa Satomi Iwata Takashi Shiihara Masaya Kubota Satoko Miyatake Eriko Koshimizu Kiyomi Nishiyama Mitsuko Nakashima Yoshinori Tsurusaki Noriko Miyake Kiyoshi Hayasaka Kazuhiro Ogata Atsuo Fukuda Naomichi Matsumoto Hirotomo Saitsu 《American journal of human genetics》2013
57.
58.
Unique Induction of CA1 LTP Components After Intake of Theanine, an Amino Acid in Tea Leaves and its Effect on Stress Response 总被引:1,自引:0,他引:1
Takeda A Tamano H Suzuki M Sakamoto K Oku N Yokogoshi H 《Cellular and molecular neurobiology》2012,32(1):41-48
Theanine, γ-glutamylethylamide, is one of the major amino acid components in green tea. This study was undertaken to evaluate
the effect of theanine intake on long-term potentiation (LTP) induction at hippocampal CA1 synapses and exposure to acute
stress. Young rats were fed water containing 0.3% theanine after birth. Key findings: Serum corticosterone level was markedly
decreased by theanine intake. Because this decrease can modify synaptic plasticity, the effect of theanine intake was examined
focused on CA1 LTP induction. CA1 LTP induced by a 100-Hz tetanus for 1 s was almost the same extent in hippocampal slices
from theanine-administered rats, whereas that induced by a 200-Hz tetanus for 1 s was significantly attenuated. 2-Amino-5-phosphonovalerate
(APV), an N-methyl-d-aspartate (NMDA) receptor antagonist, significantly attenuated CA1 LTP induced by a 200-Hz tetanus in the control rats, but
not in theanine-administered rats. Interestingly, APV completely blocked CA1 LTP induced by a 100-Hz tetanus in the control
rats, while scarcely blocking it in theanine-administered rats. These results indicate that theanine intake reduces NMDA receptor-dependent
CA1 LTP, while increasing NMDA receptor-independent CA1 LTP. Furthermore, neither 100-Hz tetanus-induced LTP nor 200-Hz tetanus-induced
LTP was attenuated in theanine-administered rats after exposure to tail suspension stress, suggesting that the lack of NMDA
receptor-dependent CA1 LTP by theanine intake is involved in ameliorating the attenuation of CA1 LTP after tail suspension.
This study is the first to indicate that theanine intake modifies the mechanism of CA1 LTP induction. 相似文献
59.
Identification of two novel GTP-binding protein alpha-subunits that lack apparent ADP-ribosylation sites for pertussis toxin 总被引:2,自引:0,他引:2
F Nakamura K Ogata K Shiozaki K Kameyama K Ohara T Haga T Nukada 《The Journal of biological chemistry》1991,266(19):12676-12681
Molecular cloning of cDNAs encoding alpha-subunits of guanine nucleotide-binding regulatory proteins (G-proteins) has revealed the existence of nine species of alpha-subunits. We have identified two additional G-protein alpha-subunits, which we refer to as GL1 alpha and GL2 alpha, by isolating bovine liver cDNA clones that cross-hybridized at reduced stringency with bovine Gi1 alpha-subunit cDNA. The deduced amino acid sequences of GL1 alpha and GL2 alpha share 83% identity with each other and show 45-55% identity with those of other known G-protein alpha-subunits. Both GL1 alpha and GL2 alpha lack a consensus site for ADP-ribosylation by pertussis toxin. Messenger RNA corresponding to GL2 alpha was detected in all tissues examined, but GL1 alpha mRNA was detected only in liver, lung, and kidney. Antiserum prepared against a synthetic pentadecapeptide corresponding to the deduced carboxyl terminus of GL2 alpha specifically reacted with a 40-kDa protein in mouse liver, brain, lung, heart, kidney, and spleen. The amount of the 40-kDa protein was highest in brain and lung. We suggest that GL1 alpha and GL2 alpha are new members of a subfamily of pertussis toxin-insensitive G-proteins. 相似文献