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11.
Darío C. Colautti Leandro Miranda Mariano Gonzalez-Castro Vanina Villanova Carlos A. Strüssmann Miguel Mancini Tomas Maiztegui Gustavo Berasain Ricardo Hattori Fabian Grosman Pablo Sanzano Ismael Lozano Sabina L. Vegh Victor Salinas Omar Del Ponti Pamela del Fresno Priscila Minotti Yoji Yamamoto Claudio R. M. Baigún 《Journal of fish biology》2020,96(1):202-216
In South America, the order Atheriniformes includes the monophyletic genus Odontesthes with 20 species that inhabit freshwater, estuarine and coastal environments. Pejerrey Odontesthes argentinensis is widely distributed in coastal and estuarine areas of the Atlantic Ocean and is known to foray into estuaries of river systems, particularly in conditions of elevated salinity. However, to our knowledge, a landlocked self-sustaining population has never been recorded. In this study, we examined the pejerrey population of Salada de Pedro Luro Lake (south-east of Buenos Aires Province, Argentina) to clarify its taxonomic identity. An integrative taxonomic analysis based on traditional meristic, landmark-based morphometrics and genetic techniques suggests that the Salada de Pedro Luro pejerrey population represents a novel case of physiological and morphological adaptation of a marine pejerrey species to a landlocked environment and emphasises the environmental plasticity of this group of fishes. 相似文献
12.
Muhammad Farooq Hiroyuki Nakai Atsushi Fujimoto Hiroki Fujikawa Klaus Wilbrandt Kjaer Shahid Mahmood Baig Yutaka Shimomura 《Human genetics》2013,132(11):1253-1264
All TGF-beta family members have a prodomain that is important for secretion. Lack of secretion of a TGF-beta family member GDF5 is known to underlie some skeletal abnormalities, such as brachydactyly type C that is characterized by a huge and unexplained phenotypic variability. To search for potential phenotypic modifiers regulating secretion of GDF5, we compared cells overexpressing wild type (Wt) GDF5 and GDF5 with a novel mutation in the prodomain identified in a large Pakistani family with Brachydactyly type C and mild Grebe type chondrodyslplasia (c527T>C; p.Leu176Pro). Initial in vitro expression studies revealed that the p.Leu176Pro mutant (Mut) GDF5 was not secreted outside the cells. We subsequently showed that GDF5 was capable of forming a complex with latent transforming growth factor binding proteins, LTBP1 and LTBP2. Furthermore, secretion of LTBP1 and LTBP2 was severely impaired in cells expressing the Mut-GDF5 compared to Wt-GDF5. Finally, we demonstrated that secretion of Wt-GDF5 was inhibited by the Mut-GDF5, but only when LTBP (LTBP1 or LTBP2) was co-expressed. Based on these findings, we suggest a novel model, where the dosage of secretory co-factors or stabilizing proteins like LTBP1 and LTBP2 in the microenvironment may affect the extent of GDF5 secretion and thereby function as modifiers in phenotypes caused by GDF5 mutations. 相似文献
13.
1. A significant amount of 32Pi is incorporated into ADP fraction if mitochondrial phosphorylation is allowed to proceed solely dependent on the endogenous adenine nucleotides even in the absence of uncouplers or inhibitors of oxidative phosphorylation. This formation of [32P]ADP is accompanied by a significant labelling of the GTP fraction as well as by a decrease in mitochondrial AMP.2. A good correlation, highly significant on a statistical basis, is obtained between the incorporation of 32Pi into ADP on the one hand and the oxidation of [1-14C]glutamate to 14CO2 on the other, under a wide variety of conditions of respiration, suggesting that the substrate-level phosphorylation linked to the oxidation of 2-oxoglutarate leads to the phosphorylation of AMP in rat liver mitochondria.3. Since intramitochondrial GTP is not directly labelled by the [32P]ATP added, it is concluded that neither nucleoside diphosphokinase (ATP:nucleoside diphosphate phosphotransferase, EC 2.7.4.6) nor adenylate kinase (ATP:AMP phosphotransferase, EC 2.7.4.3) is functioning in such an EDTA-containing medium as employed in the present study because of lack of the enzymes inside the inner membrane. This not only indicates that ATP never serves as a phosphate donor for the observed phosphorylation of AMP, but also, along with several other lines of evidence, lends strong support to the view that [32P]GTP generated as a result of the substrate-level phosphorylation is a direct precursor of [32P]ADP through the mediation of GTP:AMP phosphotransferase, which has been verified to be located inside the inner membrane by the significant labelling of GTP by [32P]ADP. 相似文献
14.
Type 2 diabetes (T2D) is a prevalent metabolic disorder across the globe. Research is underway on various aspects including genetics to understand and control the global epidemic of diabetes. Recently, several SNPs in various genes have been associated with T2D. These association studies are mainly carried out in the developed countries through Genome Wide Association Scans, with follow-up replication/validation studies by high-throughput genotyping techniques (e.g. Taqman Technology). Although, similar studies could be conducted in developing countries, however, the limiting factors are the associated cost and expertise. These factors hamper research into the genetic association and replication studies from low-income countries to figure out the role of putatively associated SNPs in diabetes. Although, there are several SNP detection methods (e.g. Taqman assay, Dot-blot, PCR-RFLP, DGGE, SSCP) but these are either expensive or labor intensive or less sensitive. Hence, our aim was to develop a low-cost method for the validation of PPARG (Pro12Ala, CCA>GCA) SNP (rs1801282) for its association with T2D. Here, we developed a cost-effective and rapid amplification refractory mutation specific-PCR (ARMS-PCR) method for this SNP detection. We successfully genotyped PPARG SNPs (Pro12Ala) in human samples and the validity of this method was confirmed by DNA sequencing of a few representative samples for the three different genotypes. Furthermore, ARMS-PCR was applied to T2D patients and control samples for the screening of this SNP. 相似文献
15.
16.
Structure and function of chloroplasts are known to after during senescence. The senescence-induced specific changes in light harvesting antenna of photosystem II (PSII) and photosystem I (PSI) were investigated in Cucumis cotyledons. Purified light harvesting complex II (LHCII) and photosystem I complex were isolated from 6-day non-senescing and 27-day senescing Cucumis cotyledons. The chlorophyll a/b ratio of LHCII obtained from 6-day-old control cotyledons and their absorption, chlorophyll a fluorescence emission and the circular dichroism (CD) spectral properties were comparable to the LHCII preparations from other plants such as pea and spinach. The purified LHCII obtained from 27-day senescing cotyledons had a Chl a/b ratio of 1.25 instead of 1.2 as with 6-day LHCII and also exhibited significant changes in the visible CD spectrum compared to that of 6-day LHCII, indicating some specific alterations in the organisation of chlorophylls of LHCII. The light harvesting antenna of photosystems are likely to be altered due to aging. The room temperature absorption spectrum of LHCII obtained from 27-day senescing cotyledons showed changes in the peak positions. Similarly, comparison of 77K chlorophyll a fluorescence emission characteristics of LHCII preparation from senescing cotyledons with that of control showed a small shift in the peak position and the alteration in the emission profile, which is suggestive of possible changes in energy transfer within LHCII chlorophylls. Further, the salt induced aggregation of LHCII samples was lower, resulting in lower yields of LHCII from 27-day cotyledons than from normal cotyledons. Moreover, the PSI preparations of 6-day cotyledons showed Chl a/b ratios of 5 to 5.5, where as the PSI sample of 27-day cotyledons had a Chl a/b ratio of 2.9 suggesting LHCII association with PSI. The absorption, fluorescence emission and visible CD spectral measurements as well as the polypeptide profiles of 27-day cotyledon-PSI complexes indicated age-induced association of LHCII of PSII with PSI obtained from 27-day cotyledons. We modified our isolation protocols by increasing the duration of detergent Triton X-100 treatment for preparing the PSI and LHCII complexes from 27-day cotyledons. However, the PSI complexes isolated from senescing samples invariably proved to have significantly low Chl a/b ratio suggesting an age induced lateral movement and possible association of LHCII with PSI complexes. The analyses of polypeptide compositions of LHCII and PSI holocomplexes isolated from 6-day control and 27-day senescing cotyledons showed distinctive differences in their profiles. The presence of 26-28 kDa polypeptide in PSI complexes from 27-day cotyledons, but not in 6-day control PSI complexes is in agreement with the notion that senescence induced migration of LHCII to stroma lamellae and its possible association with PSI. We suggest that the migration of LHCII to the stroma lamellae region and its possible association with PSI might cause the destacking and flattening of grana structure during senescence of the chloroplasts. Such structural changes in light harvesting antenna are likely to alter energy transfer between two photosystems. The nature of aging induced migration and association of LHCII with PSI and its existence in other senescing systems need to be estimated in the future. 相似文献
17.
Uzma Saqib Rajkumar Savai DongFang Liu Sreeparna Banerjee Mirza S. Baig 《Journal of cellular biochemistry》2019,120(2):1522-1526
Proteinase-activated receptor 2 (PAR-2) is a G protein–coupled receptor activated by both trypsin and a specific agonist peptide, SLIGKV-NH2. It has been linked to various pathologies, including pain and inflammation. Several peptide and peptidomimetic agonizts for PAR-2 have been developed exhibiting high potency and efficacy. However, the number of PAR-2 antagonists is smaller. We screened the Food and Drug Administration library of approved compounds to retrieve novel antagonists for repositioning in the PAR-2 structure. The most efficacious compound bicalutamide bound to the PAR-2 binding groove near the extracellular domain as observed in the in silico studies. Further, it showed reduced Ca2+ release in trypsin activated cells in a dose-dependent manner. Hence, bicalutamide is a novel and potent PAR-2 antagonist which could be therapeutically useful in blocking multiple pathways diverging from PAR-2 signaling. Further, the novel scaffold of bicalutamide represents a new molecular structure for PAR-2 antagonism and can serve as a basis for further drug development. 相似文献
18.
Uzma Saqib Syed M. Faisal Rohit Saluja Mirza S. Baig 《Journal of cellular biochemistry》2019,120(1):452-460
The benefits associated with resveratrol (Resv; 3,4′,5-trihydroxy-trans-stilbene) are known for a long time. The therapeutic properties of Resv are observed in diseases like cancer, neurological disorders, atherosclerosis, aging, inflammation, etc. Multiple studies suggest that the beneficial properties of Resv are due to its binding to targets in multiple pathways. The same has been reflected in inflammation, where Resv has been shown to inhibit nuclear factor κ light-chain enhancer of activated B cells in the toll-like receptor 4 (TLR4) pathway. There are multiple cellular targets which bind to Resv, however the mode and the key interactions involved remain elusive for many of them. In the current work, we have investigated the structural insights of Resv with three of its binding partners involved in the inflammatory TLR4 signaling pathway. Through a structure-based modelling and molecular dynamics study, we have unraveled the molecular and atomic interactions involved in the Resv-binary complexes of inhibitor of κB kinase, cyclooxygeanse-2, and tank-binding kinase I, all three of which are key players in TLR4 inflammatory signaling. This study is the latest addition to the investigations of the structural partners of Resv and its molecular interactions. 相似文献
19.
Atherosclerosis is a chronic inflammatory disease arising due to an imbalance in lipid metabolism and maladaptive immune response driven by the accumulation of cholesterol-laden macrophages in the artery wall. Interactions between monocytes/macrophages and endothelial cells play an essential role in the pathogenesis of atherosclerosis. In our current study, nitric oxide synthase 1 (NOS1)-derived nitric oxide (NO) has been identified as a regulator of macrophage and endothelial cell interaction. Oxidized LDL (OxLDL) activates NOS1, which results in the expression of CD40 ligand in macrophages. OxLDL-stimulated macrophages produce some soluble factors which increase the CD40 receptor expression in endothelial cells. This increases the interaction between the macrophages and endothelial cells, which leads to an increase in the inflammatory response. Inhibition of NOS1-derived NO might serve as an effective strategy to reduce foam cell formation and limit the extent of atherosclerotic plaque expansion. 相似文献
20.
Dental rehabilitation of a completely edentulous geriatric patient has always been a challenge to the clinician, especially in treating those with higher expectations and demands. Treatment duration and the amount of residual alveolar bone available are often important considerations when planning for dental implant-based fixed treatment for these patients. With the introduction of zygomatic implants, a graftless alternative solution has emerged for deficient maxillary bone with provision for immediate loading. This article describes the treatment of a completely edentulous elderly patient using zygomatic implants in conjunction with conventional implants. The implants were immediately loaded using a definitive acrylic resin fixed denture reinforced with a cast metal framework, to provide function and aesthetics. 相似文献