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71.
Paul REL Lafond T Müller-Graf CDM Nithiuthai S Brey PT Koella JC 《BMC evolutionary biology》2004,4(1):1-13
Background
Theoretical studies suggest that direct and indirect selection have the potential to cause substantial evolutionary change in female mate choice. Similarly, sexual selection is considered a strong force in the evolution of male attractiveness and the exaggeration of secondary sexual traits. Few studies have, however, directly tested how female mate choice and male attractiveness respond to selection. Here we report the results of a selection experiment in which we selected directly on female mating preference for attractive males and, independently, on male attractiveness in the guppy, Poecilia reticulata. We measured the direct and correlated responses of female mate choice and male attractiveness to selection and the correlated responses of male ornamental traits, female fecundity and adult male and female survival.Results
Surprisingly, neither female mate choice nor male attractiveness responded significantly to direct or to indirect selection. Fecundity did differ significantly among lines in a way that suggests a possible sexually-antagonistic cost to male attractiveness.Conclusions
The opportunity for evolutionary change in female mate choice and male attractiveness may be much smaller than predicted by current theory, and may thus have important consequences for how we understand the evolution of female mate choice and male attractiveness. We discuss a number of factors that may have constrained the response of female choice and male attractiveness to selection, including low heritabilities, low levels of genetic (co)variation in the multivariate direction of selection, sexually-antagonistic constraint on sexual selection and the "environmental covariance hypothesis".72.
Joana Abrantes Rita Ferreira Fábio Trindade António Barros Pedro Gomes Bruno Colaço Francisco Amado Pedro J. Esteves Rui Vitorino 《Proteomics》2015,15(9):1598-1607
Despite the importance of saliva in the regulation of oral cavity homeostasis, few studies have been conducted to quantitatively compare the saliva of different mammal species. Aiming to define a proteome signature of mammals’ saliva, an in‐depth SDS‐PAGE–LC coupled to MS/MS (GeLC–MS/MS) approach was used to characterize the saliva from primates (human), carnivores (dog), glires (rat and rabbit), and ungulates (sheep, cattle, horse). Despite the high variability in the number of distinct proteins identified per species, most protein families were shared by the mammals studied with the exception of cattle and horse. Alpha‐amylase is an example that seems to reflect the natural selection related to digestion efficacy and food recognition. Casein protein family was identified in all species but human, suggesting an alternative to statherin in the protection of hard tissues. Overall, data suggest that different proteins might assure a similar role in the regulation of oral cavity homeostasis, potentially explaining the specific mammals’ salivary proteome signature. Moreover, some protein families were identified for the first time in the saliva of some species, the presence of proline‐rich proteins in rabbit's saliva being a good example. 相似文献
73.
74.
Y Deng J Zhao D Sakurai KM Kaufman JC Edberg RP Kimberly DL Kamen GS Gilkeson CO Jacob RH Scofield CD Langefeld JA Kelly ME Alarcón-Riquelme BIOLUPUS GENLES Networks JB Harley TJ Vyse BI Freedman PM Gaffney KM Sivils JA James TB Niewold RM Cantor W Chen BH Hahn EE Brown PROFILE BP Tsao 《Arthritis research & therapy》2012,14(Z3):A5
75.
76.
Hernández Pérez A E Cerna Chávez JC Delgado Ortiz M Beltrán Beache LM Tapia Vargas YM Ochoa Fuentes 《Phyton》2019,88(1):11-13
Mexico is the main producer, consumer and exporter
of avocado in the world, being Michoacan the main producer state
contributing more than 80% of the national production. There
are phytopathogens that decimate the production causing the
death of the tree. Root samples were collected in avocado trees
that showed the characteristic symptomatology of the disease
known as avocado sadness, the sampling was carried out in four
of the main avocado producing towns, in the state of Michoacan,
Mexico. The isolation consisted in sowing root tissue in Petri
dishes with V8®-PARPH culture medium, subsequently they were
identified morphologically and for species level it was determined
by molecular biology, with the PCR-ITS technique. Pathogenicity
tests were performed in triplicate with avocado seedlings with more
than six leaves. After 24 hours, the inoculated plants expressed
decay in the apical part, after 120 hours the leaves showed yellowing
and after 15 days there was a generalized wilt on the stem and
leaves, re-isolating the phytopathogen Phytopythium vexans.
This study confirms the first report of the oomycete P. vexans
affecting avocado trees in the most important producing region of
the Mexican Republic. 相似文献
77.
Litia A. Carvalho Louise C. Vitorino Roberta P.M. Guimarães Silvana Allodi Ricardo A. de Melo Reis Leny A. Cavalcante 《Biochemical and biophysical research communications》2014
We examined the effects of conditioned medium from olfactory ensheathing glia (OEGCM) on the differentiation of oligodendrocytes in mixed cultures of early postnatal hippocampi. Differentiation was judged from the numerical density (ND) of cells immunoreactive to 2′3′ cyclic nucleotide 3′phosphodiesterase (CNPase) and O4 antibodies. NDs increased according to inverted-U dose–response curves, particularly for CNPase+ cells (9-fold at optimal dilution) and these changes were blocked by inhibitors of ERK1, p38-MAPK, and PI3K. Our results raise the possibility that OEG secreted factor(s) may counteract demyelination induced by trauma, neurodegenerative diseases, and advanced age, and should stimulate novel methods to deliver these factors and/or potentiating chemicals. 相似文献
78.
Patrícia de Sousa-Pereira Joana Abrantes Ana Pinheiro Bruno Cola?o Rui Vitorino Pedro J. Esteves 《PloS one》2014,9(10)
Cystatins are a family of inhibitors of cysteine peptidases that comprises the salivary cystatins (D and S-type cystatins) and cystatin C. These cystatins are encoded by a multigene family (CST3, CST5, CST4, CST1 and CST2) organized in tandem in the human genome. Their presence and functional importance in human saliva has been reported, however the distribution of these proteins in other mammals is still unclear. Here, we performed a proteomic analysis of the saliva of several mammals and studied the evolution of this multigene family. The proteomic analysis detected S-type cystatins (S, SA, and SN) in human saliva and cystatin D in rat saliva. The evolutionary analysis showed that the cystatin C encoding gene is present in species of the most representative mammalian groups, i.e. Artiodactyla, Rodentia, Lagomorpha, Carnivora and Primates. On the other hand, D and S-type cystatins are mainly retrieved from Primates, and especially the evolution of S-type cystatins seems to be a dynamic process as seen in Pongo abelii genome where several copies of CST1-like gene (cystatin SN) were found. In Rodents, a group of cystatins previously identified as D and S has also evolved. Despite the high divergence of the amino acid sequence, their position in the phylogenetic tree and their genome organization suggests a common origin with those of the Primates. These results suggest that the D and S type cystatins have emerged before the mammalian radiation and were retained only in Primates and Rodents. Although the mechanisms driving the evolution of cystatins are unknown, it seems to be a dynamic process with several gene duplications evolving according to the birth-and-death model of evolution. The factors that led to the appearance of a group of saliva-specific cystatins in Primates and its rapid evolution remain undetermined, but may be associated with an adaptive advantage. 相似文献
79.
Carvalho AF Pinto MP Grou CP Vitorino R Domingues P Yamao F Sá-Miranda C Azevedo JE 《Molecular biotechnology》2012,51(3):254-261
Research in the ubiquitin field requires large amounts of ubiquitin-activating enzyme (E1) for in vitro ubiquitination assays. Typically, the mammalian enzyme is either isolated from natural sources or produced recombinantly using baculovirus/insect cell protein expression systems. Escherichia coli is seldom used to produce mammalian E1 probably due to the instability and insolubility of this high-molecular mass protein. In this report, we show that 5-10 mg of histidine-tagged mouse E1 can be easily obtained from a 1 l E. coli culture. A low temperature during the protein induction step was found to be critical to obtain an active enzyme. 相似文献
80.
The present study aimed the evaluation of saliva sample pre-treatment, in particular the sample clearance usually performed by centrifugation, to the contribution of salivary proteome and peptidome. Using in-gel and off-gel approaches, a large content of salivary proteins was detected in the pellet fraction that is usually discarded. In addition, chaotropic/detergent treatment in combination with sonication, before the centrifugation step, resulted in salivary complex disruption and consequently in the extraction of high amounts of proteins. Based on this data, we suggest the use of urea/detergent with sonication as a standard saliva sample pre-treatment procedure. We also described a procedure to extract salivary peptides which can be performed even after saliva sample treatment with chaotropic/detergents. In overall, we reported for the first time the contribution of the pellet fraction to the whole saliva proteome. iTRAQ analysis highlighted a higher number of different peptides as well as distinct quantities of each protein class when after sample treatment with urea and sonication, acetone precipitation followed by solubilization with acetonitrile/HCl was performed. 相似文献