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1.
The precise regulation of synapse maintenance is critical to the development and function of neuronal circuits. Using an in vivo RNAi screen targeting the Drosophila kinome and phosphatome, we identify 11 kinases and phosphatases controlling synapse stability by regulating cytoskeletal, phospholipid, or metabolic signaling. We focus on casein kinase 2 (CK2) and demonstrate that the regulatory (β) and catalytic (α) subunits of CK2 are essential for synapse maintenance. CK2α kinase activity is required in the presynaptic motoneuron, and its interaction with CK2β, mediated cooperatively by two N-terminal residues of CK2α, is essential for CK2 holoenzyme complex stability and function in vivo. Using genetic and biochemical approaches we identify Ankyrin2 as a key presynaptic target of CK2 to maintain synapse stability. In addition, CK2 activity controls the subcellular organization of individual synaptic release sites within the presynaptic nerve terminal. Our study identifies phosphorylation of structural synaptic components as a compelling mechanism to actively control the development and longevity of synaptic connections. 相似文献
2.
Abstract— 5-HT was injected intravenously in rats (10 mg/kg) and a marked increase in brain 5-HT and 5-HIAA was observed. For the first 10 min after injection the penetration of 5-HT into the brain and formation of 5-HIAA is evident. After 10 min degradation of exogenous 5-HT and elimination of 5-HIAA are prominent. Metabolism of exogenous 5-HT in the brain is very fast (half-life between 5 and 10 min; completely metabolized in approximately 80 min). The importance of these results in explaining the permeability of blood-brain barrier to 5-HT is discussed. Experiments on brain slices show that 5-HT is more readily metabolized in brain tissue than eliminated into incubation medium. In contrast, 5-HIAA very easily leaves brain tissue. 相似文献
3.
Mirjana D. Mosić Jelena Đ. Trifković Petar M. Ristivojević Dušanka M. Milojković-Opsenica 《化学与生物多样性》2023,20(3):e202201141
The aim of this study is to develop a rapid, effect-directed screening method for quality assessment of bee pollen-honey mixtures. The comparative antioxidant potential and phenolic content of honey, bee pollen, and the bee pollen-honey mixtures, was performed using spectrophotometry. The total phenolic content and antioxidative activity of bee pollen-honey mixtures with 20 % bee pollen share were in the range 3.03–3.11 mg GAE/g, and 6.02–6.96 mmol TE/kg, respectively, while mixtures with 30 % bee pollen share contained 3.92–4.18 mg GAE/g, and 9.69–10.11 mmol TE/kg. Chromatographic fingerprint of bee pollen-honey mixtures was performed by high-performance thin-layer chromatography with conditions developed by authors and reported for the first time. Fingerprint analysis hyphenated with chemometrics enabled authenticity assessments of honey in mixtures. Results indicate that bee pollen-honey mixtures represent a food with highly, both, nutritious characteristics and health-promoting effect. 相似文献
4.
Nemanja Rajčević Peđa Janaćković Srđan Bojović Vele Tešević Petar D. Marin 《化学与生物多样性》2013,10(1):144-156
The essential‐oil compositions of one Croatian and three Serbian populations of Juniperus deltoides R.P.Adams have been determined by GC/MS analysis. In total, 147 compounds were identified, representing 97.3–98.3% of the oil composition. The oils were dominated by monoterpenes, which are characteristic components for the species of the section Juniperus. Two monoterpenes, α‐pinene and limonene, were the dominant constituents, with a summed‐up average content of 49.45%. Statistical methods were used to determine the diversity of the terpene classes and the common terpenes between the newly described J. deltoides populations from Serbia and Croatia. Only reports on several specimens from this species have been reported so far, and there are no studies that treat population diversity. Cluster analysis of the oil contents of 21 terpenes showed high correlation with the geographical distribution of the populations, separating the Croatian from the Serbian populations. The comparison of the essential‐oil compositions obtained in the present study with literature data, showed the separation of J. deltoides and J. oxycedrus ssp. oxycedrus from the western Mediterranean region. 相似文献
5.
Akhtar Parveen Biswas Avratanu Petrova Nia Zakar Tomas van Stokkum Ivo H. M. Lambrev Petar H. 《Photosynthesis research》2020,144(2):247-259
Photosynthesis Research - Excitation energy transfer (EET) and trapping in Anabaena variabilis (PCC 7120) intact cells, isolated phycobilisomes (PBS) and photosystem I (PSI) complexes have been... 相似文献
6.
Biswas Avratanu Huang Xinpeng Lambrev Petar H. van Stokkum Ivo H. M. 《Photosynthesis research》2020,144(2):261-272
Photosynthesis Research - The phycobilisome (PBS) serves as the major light-harvesting system, funnelling excitation energy to both photosystems (PS) in cyanobacteria and red algae. The picosecond... 相似文献
7.
Geographically Related Variation in Epicuticular Wax Traits of Pinus nigra Populations from Southern Carpathians and Central Balkans – Taxonomic Considerations
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Zorica S. Mitić Bojan K. Zlatković Snežana Č. Jovanović Gordana S. Stojanović Petar D. Marin 《化学与生物多样性》2016,13(7):931-942
The chemical composition of epicuticular waxes of nine populations from three Pinus nigra J. F. Arnold subspecies (namely subsp. nigra, subsp. banatica (Borbás ) Novák , and subsp. pallasiana (Lamb .) Holmboe ) from Southern Carpathians and central Balkan Peninsula were analyzed using GC/MS and GC/FID chromatography, and multivariate statistical techniques with respect to biogeography and taxonomy. In the needle waxes, four primary alcohols and 14 n‐alkanes ranging from C21 to C33 were identified, and the most abundant compounds were the four odd‐numbered n‐alkanes C27, C25, C23, and C29. Multivariate statistical analyses (CDA and CA) have shown existence of three P. nigra groups and suggested clinal differentiation as a mechanism of genetic variation across a geographic area: the first group consisted of the southernmost populations of subsp. pallasiana from Macedonia, the second consisted of the northernmost subsp. banatica populations from Romania, while all populations in Serbia described as three different subspecies (nigra, banatica, and pallasiana) formed the third group together with subsp. nigra population from Bosnia and Herzegovina. According to simple linear regression, geographic latitude and four bioclimatic parameters were moderately correlated with the contents of epicuticular wax compounds that are important in population discrimination, while stepwise multiple regression showed that latitude participated in most of the regression models for predicting the composition of the epicuticular waxes. These results agree with CDA and CA analysis, and confirmed the possibility of recognition of fine geographic differentiation of the analyzed P. nigra populations. 相似文献
8.
Maria I. Alvarez‐Mora Petar Podlesniy Ellen Gelpi Renate Hukema Irene Madrigal Javier Pagonabarraga Ramon Trullas Montserrat Mila Laia Rodriguez‐Revenga 《Genes, Brain & Behavior》2019,18(5)
Fragile X‐associated tremor/ataxia syndrome (FXTAS) is a late‐onset neurodegenerative disorder that appears in at least one‐third of adult carriers of a premutation (55‐200 CGG repeats) in the fragile X mental retardation 1 (FMR1) gene. Several studies have shown that mitochondrial dysfunction may play a central role in aging and also in neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease, Huntington's disease as well as in FXTAS. It has been recently proposed that mtDNA copy number, measured by the number of mitochondrial genomes per nuclear genome (diploid), could be a useful biomarker of mitochondrial dysfunction. In order to elucidate the role of mtDNA variation in the pathogenesis of FXTAS, mtDNA copy number was quantified by digital droplet Polymerase chain reaction. In human brain samples, mtDNA levels were measured in the cerebellar vermis, dentate nucleus, parietal and temporal cortex, thalamus, caudate nucleus and hippocampus from a female FXTAS patient, a FMR1 premutation male carrier without FXTAS and from three male controls. The mtDNA copy number was further analyzed using this technology in dermal fibroblasts primary cultures derived from three FXTAS patients and three controls as well as in cortex and cerebellum of a CGG knock in FXTAS mice model. Finally, qPCR was carried out in human blood samples. Results indicate reduced mtDNA copy number in the specific brain region associated with disease progression in FXTAS patients, providing new insights into the role of mitochondrial dysfunction in the pathogenesis of FXTAS. 相似文献
9.
Ghislaine Béhar Axelle Renodon-Cornière Stanimir Kambarev Petar Vukojicic Nathalie Caroff Stéphane Corvec Barbara Mouratou Frédéric Pecorari 《Biotechnology and bioengineering》2019,116(8):1844-1855
Detection and capture methods using antibodies have been developed to ensure identification of pathogens in biological samples. Though antibodies have many attractive properties, they also have limitations and there are needs to expand the panel of available affinity proteins with different properties. Affitins, that we developed from the Sul7d proteins, are a solid class of affinity proteins, which can be used as substitutes to antibodies or to complement them. We report the generation and characterization of antibacterial Affitins with high specificity for Staphylococcus aureus. For the first time, ribosome display selections were carried out using whole-living-cell and naïve combinatorial libraries, which avoid production of protein targets and immunization of animals. We showed that Affitin C5 exclusively recognizes S. aureus among dozens of strains, including clinical ones. C5 binds staphylococcal Protein A (SpA) with a K D of 108 ± 2 nM and has a high thermostability (T m = 77.0°C). Anti-S. aureus C5 binds SpA or bacteria in various detection and capture applications, including ELISA, western blot analysis, bead-fishing, and fluorescence imaging. Thus, novel anti-bacteria Affitins which are cost-effective, stable, and small can be rapidly and fully designed in vitro with high affinity and specificity for a surface-exposed marker. This class of reagents can be useful in diagnostic and biomedical applications. 相似文献
10.