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1.
alpha 1-Proteinase inhibitor (alpha 1-PI), a member of the serine
proteinase inhibitor superfamily, has a primary role in controlling
neutrophil elastase activity within the mammalian circulation. Several
studies have indicated that the reactive center region of alpha 1-PI, the
amino acid sequence of which is critical to recognition of and binding to
target proteinases, is highly divergent within and among species. This
appears to be a consequence of accelerated rates of evolution that may have
been driven by positive Darwinian selection. In order to examine this and
other features of alpha 1-PI evolution in more detail, we have isolated and
sequenced cDNAs representing alpha 1- PI mRNAs of the mouse species Mus
saxicola and Mus minutoides and have compared these with a number of other
mammalian alpha 1-PI mRNAs. Relative to other mammalian mRNAs, the extent
of nonsynonymous substitution is generally high throughout the alpha 1-PI
mRNA molecule, indicating greater overall rates of amino acid substitution.
Within and among mouse species, the 5'-half of the mRNA, but not the
3'-half, has been homogenized by concerted evolution. Finally, the reactive
center is under diversifying or positive Darwinian selection in murid
rodents (rats, mice) and guinea pigs yet is under purifying selection in
primates and artiodactyls. The significance of these findings to alpha 1-PI
function and the possible selective forces driving evolution of serpins in
general are discussed.
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2.
Maria A. G. D. Grazziotin Glaucia B. Cabral Abdulrazak B. Ibrahim Renato B. Machado Francisco J. L. Aragão 《The Annals of applied biology》2020,176(3):268-274
Persistent decrease in the productivity of cowpea (Vigna unguiculata L.) has been partly due to attack by bruchids including Zabrotes subfasciatus and Callosobruchus maculatus. Resistance to these insects in Phaseolus vulgaris L. has been shown to be associated with arcelins, a family of seed proteins encoded by a multigenic family of lectins on the APA locus. In this work, we report the construction of an expression vector containing Arc1 gene isolated from P. vulgaris and introduced into cowpea as a strategy to confer resistance to insect attack. Following transformation and selection, feeding experiments in which C. maculatus and Z. subfasciatus were fed with transgenic (L3 and L5) and non-transgenic (control) grains showed that introduced gene protected the transgenic line. Significant differences (p < .05 and p < .01) were found in the number of eggs laid, the number of emerging insects and the loss of grain mass in L3, compared with control, for both insects. Similar observations were made in L5 with the exception of the number of laid eggs. The strategy here described may form the basis for the development of a cowpea variety tolerant to bruchids in a crop cultivated by farmers throughout Latin America and Africa. 相似文献
3.
Gerd Reuter Roland Schauer Claudia Szeiki Johannis P Kamerling Johannes FG Vliegenthart 《Glycoconjugate journal》1989,6(1):35-44
Periodate oxidation of terminalN-acetyl- andN-glycoloylneuraminic acid residues in the mucins from edible bird nest substance and pig submandibular gland, respectively, can be carried out under conditions which exclusively give rise to the formation of the C-7 analogues of these sialic acids. In contrast, the C-8 compounds can be obtained in a maximum yield of about 40%. Under identical conditions,N-glycoloylneuraminic acid is oxidized about 1.5 times faster than theN-acetylated derivative. After release of the sialic acids by acid hydrolysis, the characterization of the oxidation products was carried out by TLC, by GLC and GLC-MS of the corresponding pertrimethylsilyl derivatives, and by 500-MHz1H-NMR spectroscopy. In addition, molar response factors for GLC analysis and extinction coefficients in the orcinol/Fe3+/HCl assay were determined. 相似文献
4.
Felipe G. Grazziotin Hussam Zaher Robert W. Murphy Gustavo Scrocchi Marco A. Benavides Ya‐Ping Zhang Sandro L. Bonatto 《Cladistics : the international journal of the Willi Hennig Society》2012,28(5):437-459
We present a phylogenetic analysis of the New World dipsadids based on an expanded data matrix that includes 246 terminal taxa including 196 dipsadids. The species are sampled for eight genes (12S, 16S, cytb, nd2, nd4, bdnf, c‐mos, rag2). The data are explored using two distinct optimality procedures—maximum parsimony and maximum likelihood—and two alignment strategies—dynamic homology and static homology. Two previously unsampled dipsadid genera, Sordellina and Rhachidelus, are now included in the analysis. The definitions of the genera, Erythrolamprus, Clelia, Hypsirhynchus, Philodryas and Phimophis, and the tribes Alsophiini, Echinantherini and Conophiini, are revised. In order to maintain monophyly, the genus Umbrivaga is synonymized with Erythrolamprus, and two new genera are erected to accommodate Phimophis iglesiasi and Clelia rustica, as well as their closely related species. The West Indian genera Schwartzophis, Darlingtonia, Antillophis and Ocyophis are resurrected. © The Willi Hennig Society 2012. 相似文献
5.
Cristie Grazziotin Noschang Rachel Krolow Leticia Ferreira Pettenuzzo Mônica Colpini Ávila Andrelisa Fachin Danusa Arcego Eduardo von Pozzer Toigo Leonardo Machado Crema Luísa Amália Diehl Deusa Vendite Carla Dalmaz 《Neurochemical research》2009,34(9):1568-1574
We studied the effect of chronic caffeine on parameters related to oxidative stress in different brain regions of stressed
and non-stressed rats. Wistar rats were divided into three groups: control (receiving water), caffeine 0.3 g/L and caffeine
1.0 g/L (in the drinking water). These groups were subdivided into non-stressed and stressed (repeated restraint stress during
40 days). Lipid peroxide levels and the total radical-trapping potential were assessed, as well as antioxidant enzyme activities
superoxide dismutase, gluthatione peroxidase, and catalase in hippocampus, striatum and cerebral cortex. Results showed interactions
between stress and caffeine, especially in the cerebral cortex, since caffeine increased the activity of some antioxidant
enzymes, but not in stressed animals. We concluded that chronic administration of caffeine led, in some cases, to increased
activity of antioxidant enzymes. However, these effects were not observed in the stressed animals. 相似文献
6.
Dihydroxyacetone (DHA), a three-carbon sugar, is the browning ingredient in commercial sunless tanning formulations. DHA preparations
have been used for more than 50 years and are currently highly popular for producing temporary pigmentation resembling an
ultraviolet-induced tan. In this work, the in vitro antifungal activity of dihydroxyacetone was tested against causative agents
of dermatomycosis, more specifically against dermatophytes and Candida spp. The antifungal activity was determined by the broth microdilution method according to the Clinical and Laboratory Standards Institute guidelines for yeasts and filamentous fungi. The data obtained show that the fungicidal activity varied from 1.6 to 50 mg ml−1. DHA seems to be a promising substance for the treatment of dermatomycosis because it has antifungal properties at the same
concentration used in artificial suntan lotions. Therefore, it is a potential low-toxicity antifungal agent that may be used
topically because of its penetration into the corneal layers of the skin. 相似文献
7.
Tyrosine phosphorylation of Munc18‐1 inhibits synaptic transmission by preventing SNARE assembly 下载免费PDF全文
Marieke Meijer Bernhard Dörr Hanna CA Lammertse Chrysanthi Blithikioti Jan RT van Weering Ruud FG Toonen Thomas H Söllner Matthijs Verhage 《The EMBO journal》2018,37(2):300-320
Tyrosine kinases are important regulators of synaptic strength. Here, we describe a key component of the synaptic vesicle release machinery, Munc18‐1, as a phosphorylation target for neuronal Src family kinases (SFKs). Phosphomimetic Y473D mutation of a SFK phosphorylation site previously identified by brain phospho‐proteomics abolished the stimulatory effect of Munc18‐1 on SNARE complex formation (“SNARE‐templating”) and membrane fusion in vitro. Furthermore, priming but not docking of synaptic vesicles was disrupted in hippocampal munc18‐1‐null neurons expressing Munc18‐1Y473D. Synaptic transmission was temporarily restored by high‐frequency stimulation, as well as by a Munc18‐1 mutation that results in helix 12 extension, a critical conformational step in vesicle priming. On the other hand, expression of non‐phosphorylatable Munc18‐1 supported normal synaptic transmission. We propose that SFK‐dependent Munc18‐1 phosphorylation may constitute a potent, previously unknown mechanism to shut down synaptic transmission, via direct occlusion of a Synaptobrevin/VAMP2 binding groove and subsequent hindrance of conformational changes in domain 3a responsible for vesicle priming. This would strongly interfere with the essential post‐docking SNARE‐templating role of Munc18‐1, resulting in a largely abolished pool of releasable synaptic vesicles. 相似文献
8.
Noschang Cristie Grazziotin Krolow Rachel Pettenuzzo Leticia Ferreira Ávila Mônica Colpini Fachin Andrelisa Arcego Danusa von Pozzer Toigo Eduardo Crema Leonardo Machado Diehl Luísa Amália Vendite Deusa Dalmaz Carla 《Neurochemical research》2010,35(4):677-677
Neurochemical Research - 相似文献
9.
Juan David Bayona-Serrano Vincent Louis Viala Rhett M Rautsaw Tristan D Schramer Gesiele A Barros-Carvalho Milton Yutaka Nishiyama Jr Luciana A Freitas-de-Sousa Ana Maria Moura-da-Silva Christopher L Parkinson Felipe Gobbi Grazziotin Incio L M Junqueira-de-Azevedo 《Molecular biology and evolution》2020,37(12):3563
10.
The Brazilian Atlantic Forest is one of the world's major biodiversity hotspots and is threatened by a severe habitat loss. Yet little is known about the processes that originated its remarkable richness of endemic species. Here we present results of a large-scale survey of the genetic variation at the mitochondrial cytochrome b gene of the pitviper, jararaca lancehead (Bothrops jararaca), and two closely related insular species (Bothrops insularis and Bothrops alcatraz), endemic of this region. Phylogenetic and network analyses revealed the existence of two well-supported clades, exhibiting a southern and a northern distribution. The divergence time of these two phylogroups was estimated at 3.8 million years ago, in the Pliocene, a period of intense climatic changes and frequent fragmentation of the tropical rainforest. Our data also suggest that the two groups underwent a large size expansion between 50,000 and 100,000 years ago. However, the southern group showed a more marked signal of population size fluctuation than the northern group, corroborating evidences that southern forests may have suffered a more pronounced reduction in area in the late Pleistocene. The insular species B. alcatraz and B. insularis presented very low diversity, each one sharing haplotypes with mainland individuals placed in different subclades. Despite their marked morphological and behavioural uniqueness, these two insular species seem to have originated very recently and most likely from distinct costal B. jararaca populations, possibly associated with late Pleistocene or Holocene sea level fluctuations. 相似文献