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141.
Previous studies from this laboratory suggested that the periaqueductal gray (PAG), nucleus accumbens, and amygdala might take part in a serial, unidirectional mesolimbic loop to play their roles in pain modulation. It has been proposed that morphine injected into one of these nuclei would cause the release of opioid peptides in one nucleus after another. This working hypothesis was examined in the present study by perfusing simultaneously the PAG and the amygdala after microinjection of morphine into the N. accumbens. It was found that microinjection of morphine increased the content of immunoreactive enkephalins (ir-ENK) and immunoreactive beta-endorphin (ir-beta-EP) in the perfusate of the PAG and the amygdala. When the perfusion fluid contained 3 microM of naloxone, the increase of ir-ENK and ir-beta-EP was reduced significantly. These results indicate that the three nuclei were not serially connected in a unidirectional loop. 相似文献
142.
Induction of apoptosis by human Nbk/Bik, a BH3-containing protein that interacts with E1B 19K. 总被引:11,自引:3,他引:11 下载免费PDF全文
The E1B 19-kilodalton protein (19K protein) is a potent apoptosis inhibitor and the adenovirus homolog of Bcl-2 (E. White, Genes Dev. 10:1-15, 1996). To obtain a better understanding of the biochemical mechanism by which the E1B 19K protein regulates apoptosis, proteins that interact with 19K have been identified; one of these is Bax (J. Han, P. Sabbatini, D. Perez, L. Rao, D. Mohda, and E. White, Genes Dev. 10:461-477, 1996), and another is Bak (S. N. Farrow, J. H. M. White, I. Martinou, T. Raven, K.-T. Pun, C. J. Grinham, J.-C. Martinou, and R. Brown, Nature (London) 374:731-733, 1995). Bax and Bak are Bcl-2 family members which contain Bcl-2 homology regions 1, 2, and 3 (BH1, BH2, and BH3), which interact with E1B 19K and Bcl-2 and promote apoptosis. Like Bax and Bak, Nbk was cloned from a yeast two-hybrid screen for proteins that interact with E1B 19K. Nbk contained BH3 but not BH1 or BH2. It also interacted with Bcl-2 but not with Bax. Both Bcl-2 and E1B 19K interacted with Nbk in vitro, and this interaction was highly specific. In vivo, the Nbk and E1B 19K proteins may colocalize with cytoplasmic and nuclear membranes. Nbk expression functionally antagonized 19K-mediated inhibition of apoptotic cell death and completely prevented transformation by E1A and E1B 19K. Nbk was sufficient for induction of apoptosis in the presence of mutant p53 and thus low levels of Bax, suggesting that Nbk functions independently of Bax to induce apoptosis. Nbk may therefore represent a novel death regulator which contains only a BH3 that interacts with and antagonizes apoptosis inhibitors such as the E1B 19K protein. 相似文献
143.
144.
Jigon Han Leonid N. Ten Dong Hoon Lee In-Kyu Kang Hee-Young Jung 《Antonie van Leeuwenhoek》2018,111(10):1815-1823
A bacterial isolate was recovered from a soil sample collected in Jeollabuk-do Province, South Korea, and subjected to polyphasic taxonomic assessment. Cells of the isolate, designated strain S1-2-1-2-1T, were observed to be rod-shaped, pink in color, and Gram-stain negative. The strain was able to grow at temperature range from 10 to 30 °C, with an optimum of 25 °C, and growth occurred at pH 6–8. Comparative 16S rRNA gene sequence analysis showed that strain S1-2-1-2-1T belongs to the genus Hymenobacter, with closely related type strains being Hymenobacter daeguensis 16F3Y-2T (95.8% similarity), Hymenobacter rubidus DG7BT (95.8%), Hymenobacter soli PBT (95.7%), Hymenobacter terrenus MIMtkLc17T (95.6%), Hymenobacter terrae DG7AT (95.3%), and Hymenobacter saemangeumensis GSR0100T (95.2%). The genomic DNA G+C content of strain S1-2-1-2-1T was 63.0 mol%. The main polar lipid of this strain was phosphatidylethanolamine, the predominant respiratory quinone was menaquinone-7, and the major fatty acids were C15:0 iso (27.3%), summed feature 3 (C16:1 ω7c/C16:1 ω6c) (16.5%), C15:0 anteiso (15.3%), and C16:0 (14.7%), supporting the affiliation of this strain with the genus Hymenobacter. The results of this polyphasic analysis allowed for the genotypic and phenotypic differentiation of strain S1-2-1-2-1T from recognized Hymenobacter species. On the basis of its phenotypic properties, genotypic distinctiveness, and chemotaxonomic features, strain S1-2-1-2-1T is considered to represent a novel species of the genus Hymenobacter, for which the name Hymenobacter agri sp. nov. is proposed. The type strain is S1-2-1-2-1T (=KCTC 52739T?=?JCM 32194T). 相似文献
145.
Han Wang Qian Zhang BinBin Wang WangJun Wu Julong Wei Pinghua Li Ruihua Huang 《European journal of cell biology》2018,97(4):257-268
Recently, miR-22 was found to be differentially expressed in different skeletal muscle growth period, indicated that it might have function in skeletal muscle myogenesis. In this study, we found that the expression of miR-22 was the most in skeletal muscle and was gradually up-regulated during mouse myoblast cell (C2C12 myoblast cell line) differentiation. Overexpression of miR-22 repressed C2C12 myoblast proliferation and promoted myoblast differentiation into myotubes, whereas inhibition of miR-22 showed the opposite results. During myogenesis, we predicted and verified transforming growth factor beta receptor 1 (TGFBR1), a key receptor of the TGF-β/Smad signaling pathway, was a target gene of miR-22. Then, we found miR-22 could regulate the expression of TGFBR1 and down-regulate the Smad3 signaling pathway. Knockdown of TGFBR1 by siRNA suppressed the proliferation of C2C12 cells but induced its differentiation. Conversely, overexpression of TGFBR1 significantly promoted proliferation but inhibited differentiation of the myoblast. Additionally, when C2C12 cells were treated with different concentrations of transforming growth factor beta 1 (TGF-β1), the level of miR-22 in C2C12 cells was reduced. The TGFBR1 protein level was significantly elevated in C2C12 cells treated with TGF-β1. Moreover, miR-22 was able to inhibit TGF-β1-induced TGFBR1 expression in C2C12 cells. Altogether, we demonstrated that TGF-β1 inhibited miR-22 expression in C2C12 cells and miR-22 regulated C2C12 cell myogenesis by targeting TGFBR1. 相似文献
146.
Jing Yang Yacheng Hu Jilu Han Kan Xiao Xueqing Liu Chun Tan Qingkai Zeng Hejun Du 《Journal of fish biology》2020,96(1):175-184
The sox family is assumed to be responsible for a number of developmental systems. Genome sequencing technology makes it possible to scan sox genes and conduct characteristic analyses of different species. In fish, full characterisation of sox genes at the genome-wide level has been reported for pufferfish Takifugu rubripes, medaka Oryzias latipes, tilapia Oreochromis niloticus and channel catfish Ictalurus punctatus. However, no systematic investigation of the sox family in sturgeons (Acipenseridae) has been reported to date. This study conducted genome-wide identification of the sox genes in the Chinese sturgeon Acipenser sinensis and profiled their tissue distribution between male and female individuals. In total, 19 sox genes were identified, including soxb1, b2, c, d, e, f and h, in the Chinese sturgeon. Genomic structure analysis indicated relatively conserved exon–intron structures in each sox group and phylogenetic analysis supported the previous classification of the sox family. Most of the sox genes showed a tissue-specific expression pattern, indicating the possible involvement of Chinese sturgeon sox genes at different developmental processes such as cardiac and gonadal development. This study provides a comprehensive resource of Chinese sturgeon sox genes and enables a better understanding of the evolution and function of the sox family. 相似文献
147.
Ying Wang Yunjing Zhang Xinwan Su Qiongzi Qiu Yuan Yuan Chunhua Weng Sailan Zou Yan Tian Weidong Han Pengyuan Liu Xingyi Guo Jianhua Mao Xianghui Fu Ping Wang Weiqiang Lin 《International journal of biological sciences》2022,18(4):1491
Clear cell renal cell carcinoma (ccRCC) is a primary kidney cancer with high aggressive phenotype and extremely poor prognosis. Accumulating evidence suggests that circular RNAs (circRNAs) play pivotal roles in the occurrence and development of various human cancers. However, the expression, clinical significance and regulatory role of circRNAs in ccRCC remain largely unclear. Here we report that circDVL1 to be reduced in the serums and tissues from ccRCC patients, and to negatively correlate with ccRCC malignant features. Overexpression of circDVL1 inhibits proliferation, induces G1/S arrest, triggers apoptosis, and reduces migration and invasion in different ccRCC cells in vitro. Correspondingly, circDVL1 overexpression suppresses ccRCC tumorigenicity in a mouse xenograft model. Mechanistically, circDVL1 serves as a sponge for oncogenic miR-412-3p, thereby preventing miR-412-3p-mediated repression of its target protocadherin 7 (PCDH7) in ccRCC cells. Collectively, our results demonstrate that circDVL1 exerts tumor-suppressive function during ccRCC progression through circDVL1/miR-412-3p/PCDH7 axis, and suggest that circDVL1 could be a novel diagnostic and prognositc marker and therapeutic target for ccRCC. 相似文献
148.
149.
Hydrogen sulfide (H2S) is an important gaseous molecule in various plant developmental processes and plant stress responses. In this study, the transgenic Arabidopsis thaliana plants with modulated exp... 相似文献
150.