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211.
HSPA5/GRP78/BiP plays an important role in cell survival or tumor progression. For these reasons, HSPA5 is an emerging therapeutic target in cancer development. Here we report that HSPA5 contributes to head and neck cancer (HNC) survival via maintenance of lysosomal activity; however, a nonthermal plasma (NTP, considered as a next-generation cancer therapy)-treated solution (NTS) inhibits HNC progression through HSPA5-dependent alteration of lysosomal activity. HSPA5 prevents NTS-induced lysosome inhibition through lysosomal-related proteins or regulation of gene expression. However, NTS-induced MUL1/MULAN/GIDE/MAPL (mitochondrial ubiquitin ligase activator of NFKB 1) leads to downregulation of HSPA5 via K48-linked ubiquitination at the lysine 446 (K446) residue. MUL1 knockdown hinders NTS-induced lysosome inhibition or cytotoxicity through the reduction of HSPA5 ubiquitination in HNC cells. While MUL1 was suppressed, HSPA5 was overexpressed in tissues of HNC patients. NTS strongly inhibited HNC progression via alterations of expression of MUL1 and HSPA5, in vivo in a xenograft model. However, NTS did not induce inhibition of tumor progression or HSPA5 reduction in MUL1 knockout (KO) HNC cells which were generated by CRISPR/Cas9 system. The data provide compelling evidence to support the idea that the regulation of the MUL1-HSPA5 axis can be a novel strategy for the treatment of HNC.  相似文献   
212.
The oriental fruit fly, Bactrocera dorsalis, is a serious insect pest with diverse host range. Furthermore, its invasive and polyphagous behaviors allow this species to expand its habitats. Recent climate change and increase of international trade/transportation facilitate the species expansion from subtropical to temperate regions. Low temperature during winter appears to be the major factor limiting its expansion to temperate zones in the northern hemisphere. This study reports its remarkable ability in rapid cold-hardening (RCH) along with deep supercooling capacity. A brief exposure to 9?°C significantly enhanced cold tolerance of its larvae, pupae, and adults. RCH took 1–2?h for pupae and adults, although it took 24?h for larvae. Supercooling capacity of pupae was also enhanced by RCH treatment from ?13.4?°C to ?16.6?°C. To trace genetic factors associated with RCH, calcium/calmodulin-dependent protein kinase II (Bd-CaMKII) was identified from B. dorsalis and their expression in response to RCH treatment was analyzed. Bd-CaMKII possesses three conserved domains of kinase, calmodulin, and oligomerization. Bd-CaMKII is highly homologous to CaMKII of D. melanogaster and other tephritid flies. Expression levels of Bd-CaMKII in the larvae treated with RCH were significantly increased by approximately 5.5 folds compared to those in control larvae. In addition, expression levels of HSP70 and HSP90 were also increased in response to RCH treatment. These results along with previous studies suggest that cold-hardening of B. dorsalis is functionally associated with its supercooling capacity with increased production of cryoprotectants and HSP through regulatory activity of Bd-CaMKII.  相似文献   
213.
ObjectivesGene regulation in early embryos has been widely studied for a long time because lineage segregation gives rise to the formation of a pluripotent cell population, known as the inner cell mass (ICM), during pre‐implantation embryo development. The extraordinarily longer pre‐implantation embryo development in pigs leads to the distinct features of the pluripotency network compared with mice and humans. For these reasons, a comparative study using pre‐implantation pig embryos would provide new insights into the mammalian pluripotency network and help to understand differences in the roles and networks of genes in pre‐implantation embryos between species.Materials and methodsTo analyse the functions of SOX2 in lineage segregation and cell proliferation, loss‐ and gain‐of‐function studies were conducted in pig embryos using an overexpression vector and the CRISPR/Cas9 system. Then, we analysed the morphological features and examined the effect on the expression of downstream genes through immunocytochemistry and quantitative real‐time PCR.ResultsOur results showed that among the core pluripotent factors, only SOX2 was specifically expressed in the ICM. In SOX2‐disrupted blastocysts, the expression of the ICM‐related genes, but not OCT4, was suppressed, and the total cell number was also decreased. Likewise, according to real‐time PCR analysis, pluripotency‐related genes, excluding OCT4, and proliferation‐related genes were decreased in SOX2‐targeted blastocysts. In SOX2‐overexpressing embryos, the total blastocyst cell number was greatly increased but the ICM/TE ratio decreased.ConclusionsTaken together, our results demonstrated that SOX2 is essential for ICM formation and cell proliferation in porcine early‐stage embryogenesis.  相似文献   
214.

Key message

Bulked segregant analysis (BSA) using Affymetrix GeneChips revealed candidate genes underlying the major QTL for Phytophthora capsici resistance in Capsicum . Using the candidate genes, reliable markers for Phytophthora resistance were developed and validated.

Abstract

Phytophthora capsici L. is one of the most destructive pathogens of pepper (Capsicum spp.). Resistance of pepper against P. capsici is controlled by quantitative trait loci (QTL), including a major QTL on chromosome 5 that is the predominant contributor to resistance. Here, to maximize the effect of this QTL and study its underlying genes, an F2 population and recombinant inbred lines were inoculated with P. capsici strain JHAI1-7 zoospores at a low concentration (3 × 103/mL). Resistance phenotype segregation ratios for the populations fit a 3:1 and 1:1 (resistant:susceptible) segregation model, respectively, consistent with a single dominant gene model. Bulked segregant analysis (BSA) using Affymetrix GeneChips revealed a single position polymorphism (SPP) marker mapping to the major QTL. When this SPP marker (Phyto5SAR) together with other SNP markers located on chromosome 5 was used to confirm the position of the major QTL, Phyto5SAR showed the highest LOD value at the QTL. A scaffold sequence (scaffold194) containing Phyto5SAR was identified from the C. annuum genome database. The scaffold contained two putative NBS-LRR genes and one SAR 8.2A gene as candidates for contributing to P. capsici resistance. Markers linked to these genes were developed and validated by testing 100 F1 commercial cultivars. Among the markers, Phyto5NBS1 showed about 90 % accuracy in predicting resistance phenotypes to a low-virulence P. capsici isolate. These results suggest that Phyto5NBS1 is a reliable marker for P. capsici resistance and can be used for identification of a gene(s) underlying the major QTL on chromosome 5.  相似文献   
215.
Lee J  Bae YH  Sohn YS  Jeong B 《Biomacromolecules》2006,7(6):1729-1734
We are reporting alternating multiblock copolymers of poly(L-lactic acid)/poly(ethylene glycol) aqueous solution (> 15 wt %) undergoing sol-gel-sol transition as the temperature increases from 20 to 60 degrees C. Micelles of the multiblock copolymers (in water) are about 20 nm in radius at low temperature. They are aggregated to a larger size as the temperature increases, which should play a critical role in the sol-to-gel transition. The transition temperature and gel window were affected by the molecular weight and composition of the multiblock copolymer. In particular, the aqueous solution of an alternating multiblock copolymer (Mn approximately 6700 daltons) prepared from poly(ethylene glycol) (Mn approximately 600 daltons) and poly(L-lactic acid) (Mn approximately 1300 daltons) showed a maximum modulus at body temperature (37 degrees C). The in situ gel forming ability of the polymer aqueous solution in vivo as well as in vitro indicates that it can be a promising injectable biomaterial.  相似文献   
216.

Background

Prospective investigation of obesity and renal function decline in Asia is sparse. We examined the associations of body mass index (BMI) and waist circumference (WC) with renal function decline in a prospective study of Korean population.

Methods

A total of 454 participants who had baseline estimated glomerular filtration rate (eGFR) levels of more than 60 mL/min/1.73 m2 in Hallym Aging Study (HAS) were included and followed for 6 years. Renal function decline was defined as follows: (1) an eGFR decline ≥3 mL/min/1.73 m2/year (n = 82 cases); (2) an eGFR decrease of 20% or greater (n = 87 cases) at follow-up; (3) an eGFR decrease of 20% greater at follow-up or eGFR decline ≥3 mL/min/1.73 m2/year (n = 91 cases); and (4) an eGFR <60 mL/min/1.73 m2 at follow-up (n = 54 cases). eGFR was determined based on the Modification of Diet in Renal Disease (MDRD) Study equation. Multivariate logistic regression model was used to determine the association between obesity and renal function decline.

Results

We found that central obesity was associated with faster renal function decline. Comparing WC of >95 cm in men or >90 cm in women with ≤90 cm in men or ≤85 cm in women, ORs (95% CIs) ranged from 2.31 (1.14–4.69) to 2.78 (1.19–6.50) for the 4 definitions of renal function decline (all p-values for trend <0.05). Waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR) also was associated with renal function decline. There was no significant association of BMI with renal function decline.

Conclusions

Central obesity, but not BMI, is associated with faster renal function decline in Korean population. Our results provide important evidence that simple measurement of central fat deposition rather than BMI could predict decline in renal function in Korean population.  相似文献   
217.
Circling mice manifest profound deafness, head-tossing, and bi-directional circling behavior, which they inherit in autosomal recessive manner. Histologic examination of the inner ear reveals abnormalities of the region around the organ of Corti, spiral ganglion neurons, and outer hair cells. A genetic linkage map was constructed for an intraspecific backcross between cir and C57BL/6J mice. The cir gene was mapped to a region between D9Mit116/D9Mit15 and D9Mit38 on mouse chromosome (Chr) 9. Estimated distances between cir and D9Mit116, and between cir and D9Mit38 were 0.70 +/- 0.40 and 0.23 +/- 0.23 cM, respectively. Order of the markers was defined as follows: centromere - D9Mit182 - D9Mit51/D9Mit79/D9Mit310 - D9Mit212/D184 - D9Mit116/D9Mit15 - cir - D9Mit38 - D9Mit20 - D9Mit243 - D9Mit16 - D9Mit55/D9Mit125 - D9Mit281. On the basis of genetic mapping, we constructed a yeast artificial chromosome (YAC) contig across the cir region. The cir gene is located between the lactotransferrin (ltf) and microtubule-associated protein (map4) genes. The distal portion of mouse Chr 9 encompassing the cir region is homologous with human chromosome 3p21, which contains the Deafness, form B: Autosomal Recessive Deafness (DFNB6) locus. Therefore, the circling mouse is a potential animal model for DFNB6 deafness in humans.  相似文献   
218.
In Saccharomyces cerevisiae, the Yap family of basic leucine zipper (bZip) proteins contains eight members. The Yap family proteins are implicated in a variety of stress responses; among these proteins, Yap1 acts as a major regulator of oxidative stress responses. However, the functional roles of the remaining Yap family members are poorly understood. To elucidate the function of Yap2, we mined candidate target genes of Yap2 by proteomic analysis. Among the identified genes, FRM2 was previously identified as a target gene of Yap2, which confirmed the validity of our screening method. YNL134C and YDL124W were also identified as candidate Yap2 target genes. These genes were upregulated in strains overexpressing Yap2 and possess Yap2 target sequences in their promoter regions. Furthermore, chromatin immunoprecipitation assays showed that YNL134C and YDL124W have Yap2 binding motif. These data will help to elucidate the functional role of Yap2.  相似文献   
219.
Chronic hepatitis is a major cause of liver cancer, so earlier treatment of hepatitis might be reducing liver cancer incidence. Hepatitis can be induced in mice by treatment with Concanavalin A (Con A); the resulting liver injury causes significant CD4+ T cell activation and infiltration. In these T cells, Roquin, a ring-type E3 ubiquitin ligase, is activated. To investigate the role of Roquin, we examined Con A-induced liver injury and T cell infiltration in transgenic (Tg) mice overexpressing Roquin specifically in T cells. In Roquin Tg mice, Con A treatment caused greater increases in both the levels of liver injury enzymes and liver tissue apoptosis, as revealed by TUNEL and H&E staining, than wild type (WT) mice. Further, Roquin Tg mice respond to Con A treatment with greater increases in the T cell population, particularly Th17 cells, though Treg cell counts are lower. Roquin overexpression also enhances increases in pro-inflammatory cytokines, including IFN-γ, TNF-α and IL-6, upon liver injury. Furthermore, Roquin regulates the immune response and apoptosis in Con A induced hepatitis via STATs, Bax and Bcl2. These findings suggest that over-expression of Roquin exacerbates T-cell mediated hepatitis.  相似文献   
220.
Accumulating evidence suggests that endoplasmic reticulum (ER) stress plays a major role in the development of many diseases. A previous study indicated that the apoptotic regulator p53 is significantly increased in response to ER stress and participates in ER stress-induced apoptosis. However, the regulators of p53 expression during ER stress are still not fully understood. Here, we investigated whether p53 contributes to the impairment of Pin1 signaling under ER stress. We found that treatment with thapsigargin, a stimulator of p53 expression and an inducer of ER stress, decreased Pin1 expression in HCT116 cells. Also, we identified functional p53 response elements (p53REs) in the Pin1 promoter. Overexpression of p53 significantly decreased Pin1 expression in HCT116 cells while abolition of p53 gene expression induced Pin1 expression. Pin1 expression was significantly increased by treatment with the p53 inhibitor pifithrin-α or down-regulation of p53 expression. Taken together, ER stress decreased Pin1 expression through p53 activation, and this mechanism may be associated with ER stress-induced cell death. These data reported here support the importance of Pin1 as a potential target molecule mediating tumor development.  相似文献   
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