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991.
Hyejin Shin Dayoung Park Jiyeon Kim MinYeong Nam Sojung Kwon DaEun Um JiEun Oh Esther Youn YhongHee Shim KayUwe Wagner Jin Hyun Jun HyeRyun Kim Haengseok Song Hyunjung Jade Lim 《Cell proliferation》2022,55(10)
ObjectiveAs a component of Endosomal Sorting Complex Required for Transport (ESCRT) complex I, the tumor susceptibility gene 101 (Tsg101) carries out multiple functions. In this work, we report that oocyte‐specific deletion of tumor susceptibility gene 101 (Tsg101) leads to age‐dependent oocyte demise in mice.Materials and Method Tsg101 floxed mice (Tsg101 f/f ) were bred with Zp3 cre transgenic mice to examine oocyte‐specific roles of Tsg101. Multiple cellular and molecular biological approaches were taken to examine what leads to oocyte demise in the absence of Tsg101.ResultsThe death of oocytes from Zp3 cre /Tsg101 f/f (Tsg101 d/d thereafter) mice showed a strong correlation with sexual maturation, as gonadotropin‐releasing hormone antagonist injections improved the survival rate of oocytes from 5‐week‐old Tsg101 d/d mice. Maturation of oocytes from prepubertal Tsg101 d/d mice proceeded normally, but was largely abnormal in oocytes from peripubertal Tsg101 d/d mice, showing shrinkage or rupture. Endolysosomal structures in oocytes from peripubertal Tsg101 d/d mice showed abnormalities, with aberrant patterns of early and late endosomal markers and a high accumulation of lysosomes. Dying oocytes showed plasma membrane blebs and leakage. Blockage of endocytosis in oocytes at 4°C prevented cytoplasmic shrinkage of oocytes from Tsg101 d/d mice until 9 h. The depletion of tsg‐101 in Caenorhabditis elegans increased the permeability of oocytes and embryos, suggesting a conserved role of Tsg101 in maintaining membrane integrity.ConclusionsCollectively, Tsg101 plays a dual role in maintaining the integrity of membranous structures, which is influenced by age in mouse oocytes. Tsg101 deficiency in mouse oocytes leads to a complex phenotype involving the plasma membrane (PM). These oocytes are normal until mice reach five weeks of age when oocytes begin to show PM rupture, PM blebbing, and cytoplasmic shrinkage. PM blebbing and cytoplasmic shrinkage can be postponed with a general endocytosis block, but death ensues. In both mouse and in Caenorhabditis elegans, Tsg101 plays a crucial role in maintaining the integrity of PM. 相似文献
992.
Minseo Cho Sun Lul Kwon Young Mok Heo Young Min Lee Hanbyul Lee Changmu Kim Byoung Jun Ahn Jae-Jin Kim 《Mycobiology》2022,50(4):203
Fungi act as important decomposers in the forest environment. They recycle essential nutrients, promote plant growth through mycorrhizal relationships, and act as food for small animals. Samples of 265 indigenous fungal species were collected from Mudeungsan National Park in 2020. These species were identified based on morphological, molecular, and phylogenetic analyses using the internal transcribed spacer (ITS), nuclear large subunit rRNA (LSU), and RNA polymerase II second largest subunit (rpb2) regions. Subsequently, seven species were identified as unrecorded species in Korea: Cordyceps cicadae, Dentocorticium bicolor, Hymenochaete nanospora, Physisporinus crataegi, Rigidoporus piceicola, Russula raoultii, and Scutellinia crinita. This study reveals their detailed macro- and microscopic morphological characteristics with phylogenetic trees to report them as unrecorded species in Korea. 相似文献
993.
Prashan De Zoysa Omar Toubat Drayton C. Harvey Christopher Yi Jiang Liu Susana Cavallero YoungKwon Hong Henry M. Sucov Subramanyan Ram Kumar 《Journal of cellular and molecular medicine》2022,26(20):5181
Mesodermal progenitors in the second heart field (SHF) express Delta‐like‐ligand 4 (Dll4) that regulates Notch‐mediated proliferation. As cells of SHF lineage mature to assume endocardial and myocardial cell fates, we have shown that Dll4 expression is lost, and the subsequent expression of another Notch ligand Jagged1 regulates Notch‐mediated maturation events in the developing heart. A subset of SHF progenitors also matures to form the pharyngeal arch artery (PAA) endothelium. Dll4 was originally identified as an arterial endothelial‐specific Notch ligand that plays an important role in blood vessel maturation, but its role in aortic arch maturation has not been studied to date secondary to the early lethality observed in Dll4 knockout mice. We show that, unlike in SHF‐derived endocardium and myocardium, Dll4 expression persists in SHF‐derived arterial endothelial cells. Using SHF‐specific conditional deletion of Dll4, we demonstrate that as SHF cells transition from their progenitor state to an endothelial fate, Dll4‐mediated Notch signalling switches from providing proliferative to maturation cues. Dll4 expression maintains arterial identity in the PAAs and plays a critical role in the maturation and re‐organization of the 4th pharyngeal arch artery, in particular. Haploinsufficiency of Dll4 in SHF leads to highly penetrant aortic arch artery abnormalities, similar to those observed in the clinic, primarily resulting from aberrant reorganization of bilateral 4th pharyngeal arch arteries. Hence, we show that cells of SHF lineage that assume an arterial endothelial fate continue to express Dll4 and the resulting Dll4‐mediated Notch signalling transitions from an early proliferative to a later maturation role during aortic arch development. 相似文献
994.
995.
Noguchi E Sakamoto H Hirota T Ochiai K Imoto Y Sakashita M Kurosaka F Akasawa A Yoshihara S Kanno N Yamada Y Shimojo N Kohno Y Suzuki Y Kang MJ Kwon JW Hong SJ Inoue K Goto Y Yamashita F Asada T Hirose H Saito I Fujieda S Hizawa N Sakamoto T Masuko H Nakamura Y Nomura I Tamari M Arinami T Yoshida T Saito H Matsumoto K 《PLoS genetics》2011,7(7):e1002170
Asthma is a complex phenotype influenced by genetic and environmental factors. We conducted a genome-wide association study (GWAS) with 938 Japanese pediatric asthma patients and 2,376 controls. Single-nucleotide polymorphisms (SNPs) showing strong associations (P<1×10−8) in GWAS were further genotyped in an independent Japanese samples (818 cases and 1,032 controls) and in Korean samples (835 cases and 421 controls). SNP rs987870, located between HLA-DPA1 and HLA-DPB1, was consistently associated with pediatric asthma in 3 independent populations (P
combined = 2.3×10−10, odds ratio [OR] = 1.40). HLA-DP allele analysis showed that DPA1*0201 and DPB1*0901, which were in strong linkage disequilibrium, were strongly associated with pediatric asthma (DPA1*0201: P = 5.5×10−10, OR = 1.52, and DPB1*0901: P = 2.0×10−7, OR = 1.49). Our findings show that genetic variants in the HLA-DP locus are associated with the risk of pediatric asthma in Asian populations. 相似文献
996.
997.
Soon Lim Yun-Hee Kim Sun-Hyung Kim Suk-Yoon Kwon Haeng-Soon Lee Jin-Seog Kim Kwang-Yun Cho Kee-Yoeup Paek Sang-Soo Kwak 《Molecular breeding : new strategies in plant improvement》2007,19(3):227-239
Oxidative stress is one of the major factors causing injury to plants exposed to environmental stress. Transgenic sweetpotato
[Ipomoea batatas (L.) Lam. cv. Yulmi] plants with an enhanced tolerance to multiple environmental stresses were developed by expressing the
genes of both CuZn superoxide dismutase (CuZnSOD) and ascorbate peroxidase (APX) under the control of an oxidative stress-inducible
SWPA2 promoter in the chloroplasts of sweetpotato plants (referred to as SSA plants). SSA plants were successfully generated by
the particle bombardment method and confirmed by PCR analysis. When leaf discs of SSA plants were subjected to 5 μM methyl viologen (MV), they showed approximately 45% less damage than non-transformed (NT) plants. When 200 μM MV was sprayed onto the whole plants, SSA plants showed a significant reduction in visible damage compared to leaves of NT
plants, which were almost destroyed. The expression of the introduced CuZnSOD and APX genes in leaves of SSA plants following
MV treatment was significantly induced, thereby reflecting increased levels of SOD and APX in the chloroplasts. APX activity
in chloroplast fractions isolated from SSA plants was approximately 15-fold higher than that in their counterparts from NT
plants. SSA plants treated with a chilling stress consisting of 4°C for 24 h exhibited an attenuated decrease in photosynthetic
activity (Fv/Fm) relative to NT plants; furthermore, after 12 h of recovery following chilling, the Fv/Fm of SSA plants almost
fully recovered to the initial levels, whereas NT plants remained at a lower level of Fv/Fm activity. These results suggest
that SSA plants would be a useful plant crop for commercial cultivation under unfavorable growth conditions. In addition,
the manipulation of the antioxidative mechanism in chloroplasts can be applied to the development of various other transgenic
crops with an increased tolerance to multiple environmental stresses. 相似文献
998.
Hwang J Kim CW Son KN Han KY Lee KH Kleinman HK Ko J Na DS Kwon BS Gho YS Kim J 《FEBS letters》2004,570(1-3):47-51
CCL15 is a novel human CC chemokine and exerts its biological activities on immune cells through CCR1 and CCR3. Because a number of chemokines induce angiogenesis and endothelial cells express CCR1 and CCR3, we investigated the angiogenic activity of CCL15. Both CCL15(1-92) and N-terminal truncated CCL15(25-92) stimulate the chemotactic endothelial cell migration and differentiation, but CCL15(25-92) is at least 100-fold more potent than CCL15(1-92). Treatment with pertussis toxin (PTX), with anti-CCR1, or with anti-CCR3 antibody inhibits the CCL15(25-92)-induced endothelial cell migration. CCL15(25-92) also stimulates sprouting of vessels from aortic rings and mediates angiogenesis in the chick chorioallantoic membrane assay. Our findings demonstrate that CCL15(25-92) has in vitro and in vivo angiogenic activity, and suggest roles of the chemokine in angiogenesis. 相似文献
999.
Substantial linkage disequilibrium across the insulin-degrading enzyme locus but no association with late-onset Alzheimer's disease 总被引:12,自引:0,他引:12
Richard Abraham Amanda Myers Fabienne Wavrant-DeVrieze Marian L. Hamshere Hollie V. Thomas Helen Marshall Danielle Compton Gillian Spurlock Dragana Turic Bastiaan Hoogendoorn Jennifer M. Kwon Ronald C. Petersen Eric Tangalos Joanne Norton John C. Morris Roger Bullock Danae Liolitsa Simon Lovestone John Hardy Alison Goate Michael O'Donovan Julie Williams Michael J. Owen Lesley Jones 《Human genetics》2001,109(6):646-652
Insulin-degrading enzyme (IDE; insulysin; EC 3.4.24.56) is a 110-kDa neutral metallopeptidase that can degrade a number of peptides including beta-amyloid. The gene encoding IDE is located on chromosome 10 close to a region of linkage for late-onset Alzheimer's disease (LOAD) and thus is a functional and positional candidate for this disorder. We analysed all of the coding exons, untranslated regions and 1000 bp of 5'-flanking sequence of IDE by using denaturing high-performance liquid chromatography and sequencing. We detected eight single nucleotide polymorphisms (SNPs), three in the 5' flanking sequence and five in the coding sequence, of which three were found at lower than 5% frequency. None of them changed the amino acid sequence. We genotyped the five SNPs with allele frequencies of more than 5% in 133 Caucasian LOAD cases and 135 controls collected in the UK and 95 cases and 117 controls collected at the Mayo Clinic, Rochester, USA. Two of the SNPs were analysed in a further independent case-control sample (Washington University, St. Louis: 86 cases, 94 controls). No significant association was found with any individual SNP in any of the samples or with any haplotypes. Analysis of the marker D10S583, which maps 36 kb upstream of IDE, also failed to show association in 134 cases and 111 matched controls from the UK ( P=0.63). Strong linkage disequilibrium was detected between the five SNPs that spanned the whole of the 120-kb genomic region of IDE and one major and a number of minor haplotypes were detected in the populations studied. We conclude that IDE does not make a substantial contribution to the aetiology of LOAD and therefore cannot account for the linkage between LOAD and 10q. 相似文献
1000.