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Introduction

MicroRNAs (miRs) regulate gene expression to support important physiological functions. Significant evidences suggest that miRs play a crucial role in many pathological events and in the cell response to various stresses.

Methods

With the aim to identify new miRs induced by perturbation of intracellular calcium homeostasis, we analysed miR expression profiles of thapsigargin (TG)-treated cells by microarray. In order to identify miR-663a-regulated genes, we evaluated proteomic changes in miR-663a-overexpressing cells by two-dimensional differential in-gel electrophoresis coupled to mass spectrometric identification of the differentially represented proteins. Microarray and proteomic analyses were supported by biochemical validation.

Results

Results of microarray revealed 24 differentially expressed miRs; among them, miR-663a turned out to be by ER stress and under the control of the PERK pathway of the unfolded protein response. Proteomic analysis revealed that PLOD3, which is the gene encoding for collagen-modifying lysyl hydroxylase 3 (LH3), is regulated by miR-663a. Luciferase reporter assays demonstrated that miR-663a indeed reduces LH3 expression by targeting to 3′-UTR of PLOD3 mRNA. Interestingly, miR-663a inhibition of LH3 expression generates reduced extracellular accumulation of type IV collagen, thus suggesting the involvement of miR-663a in modulating collagen 4 secretion in physiological conditions and in response to ER stress.

Conclusion

The finding of the ER stress-induced PERK-miR-663a pathway may have important implications in the understanding of the molecular mechanisms underlying the function of this miR in normal and/or pathological conditions.
  相似文献   
64.
Mice are one of the most commonly used laboratory animals, with an extensive array of disease models in existence, including for many neuromuscular diseases. The hindlimb is of particular interest due to several close muscle analogues/homologues to humans and other species. A detailed anatomical study describing the adult morphology is lacking, however. This study describes in detail the musculoskeletal geometry and skeletal muscle architecture of the mouse hindlimb and pelvis, determining the extent to which the muscles are adapted for their function, as inferred from their architecture. Using I2KI enhanced microCT scanning and digital segmentation, it was possible to identify 39 distinct muscles of the hindlimb and pelvis belonging to nine functional groups. The architecture of each of these muscles was determined through microdissections, revealing strong architectural specialisations between the functional groups. The hip extensors and hip adductors showed significantly stronger adaptations towards high contraction velocities and joint control relative to the distal functional groups, which exhibited larger physiological cross sectional areas and longer tendons, adaptations for high force output and elastic energy savings. These results suggest that a proximo-distal gradient in muscle architecture exists in the mouse hindlimb. Such a gradient has been purported to function in aiding locomotor stability and efficiency. The data presented here will be especially valuable to any research with a focus on the architecture or gross anatomy of the mouse hindlimb and pelvis musculature, but also of use to anyone interested in the functional significance of muscle design in relation to quadrupedal locomotion.  相似文献   
65.
Summary To determine the number and frequency of mutations that occur at the cystic fibrosis locus (CF), we have examined the allele and haplotype frequencies of eight polymorphic DNA markers linked to CF in 163 Italian patients who were sub-divided according to their clinical presentations. The distribution of haplotypes for the tightly linked polymorphisms KM.19 and XV-2c differ significantly between patients with and those without pancreatic insufficiency. The haplotype found most commonly in CF chromosomes occurs much more frequently in pancreatic insufficient than in pancreatic sufficient patients. Among the 19 pancreatic sufficient patients, 6 (31.6%) show at least one copy of the rare KM.19 = 1, XV-2c = 2 haplotype, as against 16 of 138 patients (11.6%) with pancreatic insufficiency. In addition, only 5 pancreatic sufficient patients (26.3%) are homozygous for the common 2,1 haplotype, as compared with 88 patients (63.8%) with pancreatic insufficiency. These findings support the hypothesis of allelic heterogeneity at a single locus in CF and suggest that different mutations underlie the presence or absence of pancreatic insufficiency in this disorders.  相似文献   
66.
Since 1980, a large program of environmental studies has been carried out along the central part of the eastern Tyrrhenian Sea, and its adjacent shoreline. The general sedimentological, biological and geochemical characteristics of this continental shelf area have been reported elsewhere (Zurlini & Damiani, 1983). In this paper, the processes responsible for the transport of terrigenous particulate matter are considered together with the influence of this particulate matter on the benthic communities of the area.Two rivers, the Garigliano to the north and the Volturno to the south, determine the extent of major environmental sub-zones in the gulf of Gaeta. The first, influenced by the Garigliano River, is restricted to the northern and inner part of the gulf, where morphological and hydrodynamical conditions favour the accumulation of suspended matter; benthic communities are stressed, mainly due to high rates of siltation. The second sub-zone is mainly influenced by the Volturno River, which affects a very large area, spreading both north and south along the coast and up to 15 km offshore.Measured levels of trace elements are considered to be close to natural concentrations. Anthropogenic contamination appears to be related to the effects of agricultural practices on the alluvial plains and to the presence of urban settlements.  相似文献   
67.
Severe hypoglycemia with isoelectric EEG induced extensive deterioration of the energy state and gross alteration of amino acid contents on the rat cerebral and cerebellar cortex. During recovery, tissue glucose concentration returned to normal, while both lactate and pyruvate concentrations increased to above normal. In the recovery period, the ATP concentration increased but the adenine nucleotide pool remained reduced, even if the ADP and AMP contents were close to normal. Phosphocreatine was restored to normal concentration with reciprocal changes in creatine content. During recovery there was a rise in glutamate and glutamine concentrations, gamma-aminobutyrate content returning to normal value. Ammonia and aspartate decreased below normal, while alanine increased above normal. The effect of some pharmacological agents on the posthypoglycemic recovery was tested: (a) Ergot alkaloids (dihydroergocristine, dihydroergocriptine, dihydroergocornine); (b) Vinca minor alkaloids (vincamine TPS, (–) eburnamonine); (c) Rauwolfia serpentina alkaloids (reserpine, raubasine); (d) synthetic agent (piracetam). During the posthypoglycemic recovery, these different agents exhibited different, or even contrasting, interferences on glycolytic metabolites, amino acids and energy-rich phosphates. The metabolic alterations in the cerebellar cortex were qualitatively of the same character of those in neocortex. However, the metabolic alterations were less extensive and more sensitive to drug action.  相似文献   
68.
In order to investigate the molecular features involved in sigma receptors (σ-Rs) binding, new compounds based on arylalkylaminoalcoholic, arylalkenyl- and arylalkylaminic scaffolds were synthesized and their affinity towards σ1- and σ2-Rs subtypes was evaluated. The most promising compounds were also screened for their affinity at μ-opioid, δ-opioid and κ-opioid receptors. Biological results are herein presented and discussed.  相似文献   
69.
Abstract

Further contribution on the relationship between nickel and malic and malonic acids in Alyssum.—Further research has been carried out on extracts of leaves and seeds of A. bertolonii Desv., grown on serpentine and normal garden soil, in order to investigate the nature of the nickel compounds present in this plant. On the purified extracts, obtained with water and formic acid, malic and malonic acids have been determined through gas-chromatography of the trimethyl-sililderivatives; Ni, Ca, Mg and K have been analysed by atomic absorption spectrophotometry.

Both malic and malonic acids are present in the leaves of the plants collected on serpentine and therefore rich in nickel, whilst they are present only in small amounts in the plants grown in garden soil. Seeds contain mainly high levels of malic acid. Remarkable amounts of malic acid, related to a high nickel content, have been observed also in the leaves of another nickel accumulator in the genus Alyssum, i.e. A. serpyllifolium Desf. ssp. lusitanicum Dudley et P. Silva, endemic of Portugal serpentines.  相似文献   
70.
Following our results with benzopsoralens as potent photochemotherapeutic agents, we report the antiproliferative evaluation of nitrogenated isoster upon and without UVA irradiation. The evaluated pyridazinopsoralen showed a higher photochemotherapeutic activity with respect to the well-known drug, 8-MOP, and a significant cytotoxicity, also in the dark. This result enlarges the interest in this tetracyclic psoralen derivative skeleton in the search of new anticancer agents.  相似文献   
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