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941.
J.‐Y. Bae I.‐H. Ok S. Lee S. S. O. Hung T. S. Min S. C. Bai 《Zeitschrift fur angewandte Ichthyologie》2011,27(3):887-891
This study aimed to reevaluate the dietary methionine requirement by means of the plasma methionine and ammonia concentrations in surgically modified rainbow trout, Oncorhynchus mykiss. A total of 35 rainbow trout averaging 505 ± 6.5 g (initial body weight, mean ± SD) were randomly distributed into seven groups with five fish in each group. After 48 h of food deprivation, each group was fed one of seven L‐amino acid‐based diets containing graded levels of methionine (0.25, 0.40, 0.50, 0.60, 0.70, 0.80 or 0.95% of diet, dry matter bases) by intubation at 1% bodyweight. Blood samples were taken at 0, 5 and 24 h after intubation. Post‐prandial plasma free methionine concentrations (PPmet, 5 h after intubation) and post‐absorptive plasma free methionine concentrations (PAmet, 24 h after intubation) of fish fed diets containing 0.60% or more methionine were significantly (P < 0.05) higher than those of fish fed diets containing 0.50% or less methionine. PPmet and PAmet in fish fed diets containing 0.60% or higher methionine were not significantly different except the PPmet of fish fed a diet containing 0.95% methionine. Post‐prandial plasma ammonia concentrations (PPA, 5 h after intubation) of fish fed diets containing 0.70% or more methionine were significantly higher than those of fish fed diets containing 0.60% or less methionine, and PPA of fish fed diets containing 0.25% and up to 0.60% methionine were not significantly different from each other. Broken‐line model analyses on PPmet, PAmet, and PPA indicated that the dietary methionine requirement of rainbow trout was between 0.59% (1.69) and 0.67% (1.91) of diets (% dietary protein bases) when the diets contained 0.5% cystine. 相似文献
942.
Kim JH Kim K Youn BU Jin HM Kim JY Moon JB Ko A Seo SB Lee KY Kim N 《The Biochemical journal》2011,433(2):253-262
The MTM (myotubularin)/MTMR (myotubularin-related) protein family is comprised of 15 lipid phosphatases, of which nine members are catalytically active. MTMs are known to play a fundamental role in human physiology as gene mutations can give rise to X-linked myotubular myopathy or Charcot-Marie-Tooth disease, which manifest in skeletal muscle or in peripheral neurons respectively. Interestingly, studies have shown MTMR2 and MTMR5, two MTM family members, to be highly expressed in the testis, particularly in Sertoli and germ cells, and knockout of either gene resulted in spermatogenic defects. Other studies have shown that MTMR2 functions in endocytosis and membrane trafficking. In the testis, MTMR2 interacts and co-localizes with c-Src/phospho-Src-(Tyr?1?), a non-receptor protein tyrosine kinase that regulates the phosphorylation state of proteins at the apical ES (ectoplasmic specialization), a unique type of cell junction found between Sertoli cells and elongating/elongated spermatids. In the present review, we highlight recent findings that have made a significant impact on our understanding of this protein family in normal cell function and in disease, with the emphasis on the role of MTMs and MTMRs in spermatogenesis. We also describe a working model to explain how MTMR2 interacts with other proteins such as c-Src, dynamin 2, EPS8 (growth factor receptor pathway substrate 8) and ARP2/3 (actin-related protein 2/3) at the apical ES and the apical TBC (tubulobulbar complex; tubular-like invaginations that function in the disassembly of the apical ES and in the recycling of its components) to regulate spermiation at late stage VIII of the seminiferous epithelial cycle. 相似文献
943.
Nam GH Ahn K Bae JH Han K Lee CE Park KD Lee SH Cho BW Kim HS 《Zoological science》2011,28(4):276-280
Muscle glycogen Phosphorylase (PYGM) has been shown to catalyze the degradation of glycogen to glucose-1-phosphate. The PYGM gene can contribute to providing energy to the body by disassembling the glycogen in muscle. Here, we analyzed the genomic structure and expression of the PYGM gene in the thoroughbred horse. The PYGM gene, containing several transposable elements (MIRs, LINEs, and MERs), was highly conserved in mammalian genomes. In order to understand the expression of the horse PYGM gene, we performed quantitative RT-PCR using 11 thoroughbred horse tissue samples. The horse PYGM gene was broadly expressed in all tissues tested. In particular, the highest expression of the horse PYGM gene was observed in skeletal muscle tissue relative to the other tissues. Interestingly, the horse PYGM gene contains fewer mobile elements than its human ortholog, resulting in an increase in the structural stability of the PYGM gene sequence. This study provides insights into the genomic structure of the horse PYGM gene that may be useful in future studies of its association with exercise capability. 相似文献
944.
945.
Sohn WJ Yamamoto H Shin HI Ryoo ZY Lee S Bae YC Jung HS Kim JY 《Cell and tissue research》2011,344(2):271-277
Epithelial appendages on palatal rugae develop during mouse palatogenesis through epithelial thickening and pattern formation.
Recently, the patterned formation of nine rugae was observed together with the specific expression patterns of Shh in rodents. However, no crucial evidence was found for a direct association between Shh expression and the distinct structural formation of rugae. In order to reveal possible relationships, we investigated the
morphological changes of rugae and expression patterns of Shh directly by in vitro organ culture at embryonic day 13 (E13) for 2 days. To compare and examine the diverse growing aspects
of the palate and rugae, we carefully observed the detailed morphogenesis, with cell proliferation of the rugae occurring
between E13 and E14.5. After 2 days of cultivation at E13, DiI micro-injections revealed that the middle part of the palate,
adjacent to the upper molar-forming region, contributed to the formation of the subsequent structure of rugae by extensive
cell rearrangement and proliferation within the epithelium in the preferred anteroposterior direction. The results also defined
the intimate relationship between Shh expression and rugae formation. 相似文献
946.
Yong Kyung LeeIm Seop Choi Jung Ok BanHwa Jeong Lee Ung Soo LeeSang Bae Han Jae Kyung JungYoung Hee Kim Ki Ho KimKi-Wan Oh Jin Tae Hong 《The Journal of nutritional biochemistry》2011,22(5):476-486
Oxidative stress induced neuronal cell death by accumulation of β-amyloid (Aβ) is a critical pathological mechanism of Alzheimer's disease (AD). Intracerebroventrical infusion of Aβ1-42 (300 pmol/day per mouse) for 14 days induced neuronal cell death and memory impairment, but pre-treatment of 4-O-methylhonokiol (4-O-MH), a novel compound extracted from Magnolia officinalis for 3 weeks (0.2, 0.5 and 1.0 mg/kg) prior to the infusion of Aβ1-42 and during the infusion dose dependently improved Aβ1-42-induced memory impairment and prevented neuronal cell death. Additionally, 4-O-MH reduced Aβ1-42 infusion-induced oxidative damages of protein and lipid but reduced glutathione levels in the cortex and hippocampus. Aβ1-42 infusion-induced activation of astrocytes and p38 mitogenic activated protein (MAP) kinase was also prevented by 4-O-MH in mice brains. In further study using culture cortical neurons, p38 MAP kinase inhibitor abolished the inhibitory effect of 4-O-MH (10 μM) on the Aβ1-42 (5 μM)-induced reactive oxidative species generation and neuronal cell death. These results suggest that 4-O-MH might prevent the development and progression of AD through the reduction of oxidative stress and neuronal cell death via inactivation of p38 MAP kinase pathway. 相似文献
947.
Kwon SW Kang SK Lee JH Bok JH Kim CH Dal Rhee S Jung WH Kim HY Bae MA Song JS Ha DC Cheon HG Kim KY Ahn JH 《Bioorganic & medicinal chemistry letters》2011,21(1):435-439
A new series of thiazolidine derivatives with an adamantyl group was synthesized and evaluated for their ability to inhibit 11β-hydroxysteroid dehydrogenase 1 (11β-HSD1). Our initial compound 5a showed a weak inhibitory activity. Significant improvements in potency were achieved by substituent modification. The potent compound 8g (E) showed good in vitro inhibitory activity toward human 11β-HSD1, selectivity toward 11β-HSD2, metabolic stability, pharmacokinetic, and safety profile. Furthermore, this compound significantly inhibited 11β-HSD1 activity in rat and monkey models, and showed improved glycemic control in KKAy mice. 相似文献
948.
Pyrococcus sp. strain NA2, isolated from a deep-sea hydrothermal vent sample, is a novel marine hyperthermophilic archaeon that grows optimally at 93 °C. The complete genome sequence of the strain contains all the genes for the tricarboxylic acid cycle except for succinate dehydrogenase/fumarate reductase, but the genome does not encode proteins involved in polysaccharide utilization. 相似文献
949.
Hong J Bae S Jhun H Lee S Choi J Kang T Kwak A Hong K Kim E Jo S Kim S 《The Journal of biological chemistry》2011,286(22):20078-20086
IL-33/IL-1F11 is a new member of the IL-1 family ligand and provokes T helper-type immune responses. IL-33 is the ligand of ST2 and IL-1 receptor accessory protein (IL-1RAcP) that triggers nuclear factor-κ light chain enhancer of activated B cells (NF-κB) and MAPK signaling. We discovered a novel short splice variant of IL-33 that was termed spIL-33. The new spIL-33 lacks exon 3 containing a proposed caspase-1 cleavage site. We isolated spIL-33 cDNA from the Huh7 human hepatocarcinoma cell line and expressed the recombinant spIL-33 protein in Escherichia coli. The recombinant spIL-33 and pro-IL-33 were not cleaved by caspase-1, unlike IL-18 (IL-1F4). The recombinant spIL-33 was constitutively active, and spIL-33-induced inflammatory cytokine production was caspase-1-independent in HMC-1 and Raw 264.7 cells. The recombinant spIL-33 induced the phosphorylation of IL-1 receptor-associated kinase (IRAK1), NF-κB, p38 MAPK, p44/42 MAPK, and JNK in a time- and dose-dependent manner. Anti-ST2 monoclonal antibody specifically blocked the spIL-33-induced cytokine production. In this study, we identified and characterized a new IL-33 splice variant, which was a constitutively active IL-33 isoform. The existence of constitutively active spIL-33 suggests that the biological activity of IL-33 could be triggered by diverse stimulations during immune responses. Further investigation of the spIL-33 expression pattern may contribute to understanding the involvement of IL-33 in inflammatory disorders. 相似文献
950.
In this study, we identified p53 as a novel TCTP-interacting protein using TCTP as bait. Also, we determined the critical binding sites between TCTP and p53. To elucidate the functional consequence of the interaction, we developed the overexpression and inhibition system of TCTP and p53 expression. Overexpression of TCTP in lung carcinoma cells reversed p53 mediated apoptosis and inhibition of TCTP expression by small interfering RNA increased apoptosis of lung carcinoma cells. Moreover, it was observed that TCTP overexpression promotes degradation of p53. These results clearly indicate that the interaction between TCTP and p53 prevents apoptosis by destabilizing p53. Thus, TCTP acts as a negative regulator of apoptosis in lung cancer.