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1.
Santi Guallar  Roger Jovani 《Ibis》2020,162(3):778-786
Passerine wing-feather moult has been studied historically in terms of its intensity, duration, timing and extent. However, little is known about variation of wing-moult phenotypes (i.e. the identity of moulted wing feathers in a given individual) within species, among moult episodes and in relation to passerine phylogeny. Here we studied 5373 wing-moult cards from 285 Holarctic and 155 Neotropical passerine species. Variation of moult phenotypes, although high, was far below that expected by chance, and the same phenotypes were repeated among individuals within and among species, suggesting the existence of shared mechanisms of moult control. We successfully classified moult phenotypes according to nine moult patterns described in the literature and found an uneven distribution between the preformative and the prealternate moult. Moult patterns were phylogenetically conserved for the preformative but not for the prealternate moult. Our results suggest differential seasonal control of bird moult with preformative moults being associated with (evolutionarily conserved) somatic demands, whereas prealternate moults are probably associated with (rapidly evolving) signalling functions.  相似文献   

2.
AIMS: A survey was conducted on the ecological distribution of bacteriocin-producing lactic acid bacteria in Miso-pastes, a typical fermented food in Japan. METHODS AND RESULTS Nine Miso-pastes were sampled for isolation of bacteriocin-producers. Almost all isolated enterococcal strains produced bacteriocins but no isolated tetragenococci did so. The bacteriocin-producing isolates were divided into nine groups by phenotypic tests. As the phenotypic characters were highly diverse, these strains could not be identified to species level on the basis of their phenotypes. The nine representative strains from each group were identified by 16S rRNA analysis. These bacteriocin-producers with one exception (Lactococcus sp.) were identified as strains of the Enterococcus faecium 'species group'. The bacteriocins of the nine strains were classified into five types according to their antibacterial spectral patterns and their SDS-PAGE profiles. The bacteriocins inhibited undesirable bacteria in Miso-pastes, such as Bacillus subtilis, but did not inhibit the useful Tetragenococcus halophila. CONCLUSIONS: The bacteriocin-producing lactic acid cocci were widespread at high frequencies in Miso-pastes. They were considered to play an important role in preventing the growth of undesirable bacteria. SIGNIFICANCE AND IMPACT OF THE STUDY: This study suggests that bacteriocin-producers act effectively as safe biopreservatives and may contribute to the biopreservation in Miso-pastes.  相似文献   

3.
Meloidogyne sp. from five pecan (Carya illinoensis) orchards in Texas were distinctive in host range and iszoyme profiles from common species of Meloidogyne but were morphologically congruent with Meloidogyne partityla Kleynhans, a species previously known only in South Africa. In addition to pecan, species of walnut (Juglans hindsii and J. regia) and hickory (C. ovata) also were hosts. No reproduction was observed on 15 other plant species from nine families, including several common hosts of other Meloidogyne spp. Three esterase phenotypes and two malate dehydrogenase phenotypes of M. partityla were identified by polyacrylamide gel electrophoresis. Each of these isozyme phenotypes was distinct from those of the more common species M. arenaria, M. hapla, M. incognita, and M. javanica.  相似文献   

4.
S V Kuryshev 《Genetika》1990,26(10):1822-1827
Electrophoretic pattern of serum proteins of northern red-backed and large-toothed voles was examined. Seven main protein zones were distinguished. In four of them variability was observed, possibly genetically determined. Polymorphism of transferrins was thoroughly studied. 6 alleles and only 7 phenotypes of this protein were found in the northern red-backed vole, while 3 alleles and 4 phenotypes were revealed in the large-toothed red-backed vole, two alleles being common. Distribution of phenotype frequencies observed in both species differs significantly from the expected value. The portion of heterozygous phenotypes is quite high in both species, being 0.304 and 0.400 in the northern red-backed and large-toothed red-backed voles, respectively. Hemoglobins of the species studied were identical in electrophoretic mobility and monomorphic.  相似文献   

5.
Nine isolates of infectious hematopoietic necrosis virus (IHNV) from three different species of Alaskan salmonids were examined for in vitro growth characteristics, the molecular weight of virion polypeptides, and serologic response to four different monoclonal antibodies developed against IHNV. The results of this study suggest that, although serologically similar, three antigenic variants of IHNV may be present in Alaska. All nine viruses were neutralized by the monoclonal antibody RB/B5. However, the viruses could be divided into three sub-groups based on the ability or inability to react with the monoclonal antibodies 193–110/B4 and NR-2. The growth characteristics of all nine viruses were similar enough to suggest there was no significant difference in phenotypes among these viruses. The molecular weights of the viral polypeptides were similar in that all had a glycoprotein (G) of 66 kd, a nucleocapsid (N) protein of 42 kd, ana a polymerase (L) of 180 kd molecular weight.  相似文献   

6.
Thirty-two phenotypes of alpha-1-antitrypsin (al-AT) controlled by 18 codominant alleles of PImac locus were identified by isoelectric focusing in 1.121 macaques of nine species. In terms of al-AT polymorphism macaque species vary markedly from nearly monomorphic (Macaca mulatta, M. arctoides) to highly polymorphic (M. nemestrina, M. fascicularis). Only 4 of 18 PImac alleles are common for two or more macaque species, the rest of the alleles are species-specific.  相似文献   

7.
c-kit蛋白在昆虫和哺乳动物生殖细胞发育中发挥着重要作用。本研究通过免疫组织化学法和生物统计方法,比较分析了隶属于直翅目蝗总科的9种蝗虫精子发生过程中c-kit蛋白表达差异。结果显示,蝗虫精子发生过程中c-kit蛋白均出现阶段特异性表达,并且在9种蝗虫种间c-kit蛋白表达出现显著差异。  相似文献   

8.
In total, 170 strains of thermophilic bacteria were isolated from deep-sea hydrothermal fields in the Pacific Ocean and a hot spring in Xiamen of China. To facilitate the identification of thermophilic strains, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of whole-cell proteins of these strains was first performed. The results showed that there exist four different protein patterns, indicating that the 170 strains might belong to four species or genera. The RAPD (random amplified polymorphic DNA) profiles of nine representative strains were consistent with those of SDS-PAGE. To further identify the species of the nine strains, their 16S rDNA sequences were analyzed. The results showed that the nine strains fell into four species of three genera, which was the same as revealed by SDS-PAGE. Therefore, SDS-PAGE of whole-cell proteins could be used as a rapid and simple method for the discrimination of thermophilic bacteria as the first step of species identification.  相似文献   

9.
RNA interference (RNAi) has become an integral part of mainstream research due to its versatility and ease of use. However, the potential nontarget effects associated with double-stranded RNAs (dsRNA) are poorly understood. To explore this, we used dsRNAs targeting the inhibitor of apoptosis (iap) gene from nine insect species and assayed their possible nontarget effects. For each assay, we used a control (dsRNA targeting the gene coding for green fluorescent protein, GFP) and a species-specific dsRNA targeting nine iap genes in insect species to evaluate target gene knockdown efficiency, apoptosis phenotype in cells and mortality in insects. Our results revealed that dsIAP efficiently knocks down iap gene expression and induces apoptosis phenotype and mortality in target insect species. In contrast, no significant knockdown of the iap gene expression, apoptosis phenotypes, or mortality were detected in cell lines developed from nontarget insects or nontarget insects treated with dsIAPs. Interestingly, even among closely related insects such as stink bugs, Nezara viridula, Halyomorpha halys, and Murgantia histrionica, with substantial sequence similarity among iap genes from these insects, no significant nontarget effects of dsIAP were observed under the conditions tested. These data demonstrate no significant nontarget effects for dsIAPs and suggest that the threat of nontarget effects of RNAi technology may not be substantial.  相似文献   

10.
Functional impairment of mitochondria and proteasomes and increased oxidative damage comprise the main pathological phenotypes of Parkinson disease (PD). Using an unbiased quantitative proteomic approach, we compared nigral mitochondrial proteins of PD patients with those from age-matched controls. 119 of 842 identified proteins displayed significant differences in their relative abundance (increase/decrease) between the two groups. We confirmed that one of these, mortalin (mthsp70/GRP75, a mitochondrial stress protein), is substantially decreased in PD brains as well as in a cellular model of PD. In addition, nine candidate mortalin-binding partners were identified as potential mediators of PD pathology. Manipulations of mortalin level in dopaminergic neurons resulted in significant changes in sensitivity to PD phenotypes via pathways involving mitochondrial and proteasomal function as well as oxidative stress.  相似文献   

11.
In this study, we demonstrate the versatility of matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOFMS) protein profiling for the species differentiation of a diverse suite of Bacillus spores. MALDI-TOFMS protein profiles of 11 different strains of Bacillus spores, encompassing nine different species, were evaluated. Bacillus species selected for MALDI-TOFMS analysis represented the spore-forming bacterial diversity of typical class 100K clean room spacecraft assembly facilities. A one-step sample treatment and MALDI-TOFMS preparation were used to minimize the sample preparation time. A library of MALDI-TOFMS spectra was created from these nine Bacillus species, the most diverse protein profiling study of the genus reported to date. Linear correlation analysis was used to successfully differentiate the MALDI-TOFMS protein profiles from all strains evaluated in this study. The MALDI-TOFMS protein profiles were compared with 16S rDNA sequences for their bacterial systematics and molecular phylogenetic affiliations. The MALDI-TOFMS profiles were found to be complementary to the 16S rDNA analysis. Proteomic studies of Bacillus subtilis 168 were pursued to identify proteins represented by the biomarker peaks in the MALDI-TOFMS spectrum. Four small, acid-soluble proteins (A, B, C, and D), one DNA binding protein, hypothetical protein ymf J, and four proteins associated with the spore coat and spore coat formation (coat JB, coat F, coat T, and spoIVA) were identified. The ability to visualize higher-molecular-mass coat proteins (10 to 25 kDa) as well as smaller proteins (<10 kDa) with MALDI-TOFMS profiling is critical for the complete and effective species differentiation of the Bacillus genus.  相似文献   

12.
Analysis of allele frequencies of nine nuclear DNA microsatellite loci in the sable (Martes zibellina) and pine marten (M. martes) demonstrated that these species from allopatric parts of the area differ with a high degree of significance, while hybridization regularly occurs between them in the sympatry zone in the Northern Urals. In total, populations of the sable and pine marten maintain genetic isolation in the sympatry area; however, individual phenotypes do not always correlate with their specific (or hybrid) belonging, which is determined by a genetic method.  相似文献   

13.
Postmating, prezygotic phenotypes, especially those that underlie reproductive isolation between closely related species, have been a central focus of evolutionary biologists over the past two decades. Such phenotypes are thought to evolve rapidly and be nearly ubiquitous among sexually reproducing eukaryotes where females mate with multiple partners. Because these phenotypes represent interplay between the male ejaculate and female reproductive tract, they are fertile ground for reproductive senescence – as ejaculate composition and female physiology typically change over an individual''s life span. Although these phenotypes and their resulting dynamics are important, we have little understanding of the proteins that mediate these phenotypes, particularly for species groups where postmating, prezygotic traits are the primary mechanism of reproductive isolation. Here, we utilize proteomics, RNAi, mating experiments, and the Allonemobius socius complex of crickets, whose members are primarily isolated from one another by postmating, prezygotic phenotypes (including the ability of a male to induce a female to lay eggs), to demonstrate that one of the most abundant ejaculate proteins (a male accessory gland-biased protein similar to a trypsin-like serine protease) decreases in abundance over a male''s reproductive lifetime and mediates the induction of egg-laying in females. These findings represent one of the first studies to identify a protein that plays a role in mediating both a postmating, prezygotic isolation pathway and reproductive senescence.  相似文献   

14.
Convergence—the independent evolution of the same trait by two or more taxa—has long been of interest to evolutionary biologists, but only recently has the molecular basis of phenotypic convergence been identified. Here, we highlight studies of rapid evolution of cryptic coloration in vertebrates to demonstrate that phenotypic convergence can occur at multiple levels: mutations, genes and gene function. We first show that different genes can be responsible for convergent phenotypes even among closely related populations, for example, in the pale beach mice inhabiting Florida''s Gulf and Atlantic coasts. By contrast, the exact same mutation can create similar phenotypes in distantly related species such as mice and mammoths. Next, we show that different mutations in the same gene need not be functionally equivalent to produce similar phenotypes. For example, separate mutations produce divergent protein function but convergent pale coloration in two lizard species. Similarly, mutations that alter the expression of a gene in different ways can, nevertheless, result in similar phenotypes, as demonstrated by sister species of deer mice. Together these studies underscore the importance of identifying not only the genes, but also the precise mutations and their effects on protein function, that contribute to adaptation and highlight how convergence can occur at different genetic levels.  相似文献   

15.
Can the complex phenotypes that characterize naturally occurring hybrid species be re-created in early-generation artificial hybrids? We address this question with three homoploid hybrid species (Helianthus anomalus, Helianthus deserticola, Helianthus paradoxus) and their ancestral parents (Helianthus annuus, Helianthus petiolaris) that are phenotypically distinct and ecologically differentiated. These species, and two synthetic hybrid populations of the ancestral parents, were characterized for morphological, physiological, and life-history traits in greenhouse studies. Among the synthetic hybrids, discriminant analysis identified a few individuals with the multitrait phenotype of the natural hybrid species: 0.7%-1.1% were H. anomalus-like, 0.5%-13% were H. deserticola-like, and only 0.4% were H. paradoxus-like. These relative frequencies mirror previous findings that genetic correlations are favorable for generating the hybrid species' phenotypes, and they correspond well with phylogeographic evidence that demonstrates multiple natural origins of H. deserticola and H. anomalus but a single origin for H. paradoxus. Even though synthetic hybrids with hybrid species phenotypes are rare, their phenotypic correlation matrices share most of the same principal components (eigenvectors), setting the stage for predictable recovery of hybrid species' phenotypes from different hybrid populations. Our results demonstrate past hybridization could have generated hybrid species-like multitrait phenotypes suitable for persistence in their respective environments in just three generations after initial hybridization.  相似文献   

16.
A two-component histidine protein kinase gene, homologous to os-1 from Neurospora crassa, was cloned and sequenced from a single ascospore isolate of Botryotinia fuckeliana. A series of nine spontaneous mutants resistant to dicarboximide fungicides was selected from this strain and characterized with respect to fungicide resistance and osmotic sensitivity. Genetic crosses of the mutants with an authentic Daf1 strain showed that the phenotypes mapped to this locus. Single point mutations (seven transitions, one transversion, and one short deletion) were detected in the alleles of the nine mutants sequenced. The mutational changes were shown to cosegregate with the dicarboximide resistance and osmotic sensitivity phenotypes in progeny obtained from crossing selected resistant strains with a sensitive strain. All mutations detected are predicted to result in amino acid changes in the coiled-coil region of the putative Daf1 histidine kinase, and it is proposed that dicarboximide fungicides target this domain.  相似文献   

17.
Samples of nine species or types of commercial grass seed straws grown in Oregon were analyzed and treated with anhydrous ammonia in the laboratory. Enzymatic digestibility of treated and untreated materials was determined using commercial cellulase and protease. The mean composition of all nine species/types (based on six each within-group replicates) was: crude protein, 5.4%; NDF, 72.2%; ADF, 43.6%; hemicellulose, 26.4%; cellulose, 34.8%; and lignin, 6.9%. Significant species/type compositional differences were found. From their composition, several of the grass straws appeared to have better nutritional value than most cereal straws. Enzymatic digestibility of all straws was improved by ammoniation (average increase, 62%). Enzymatic digestibility ranged from about 27–42% for untreated materials to 43–66% for NH3-treated products.  相似文献   

18.
The occurrence, diversity, and pathogenicity of Vibrio spp. were investigated in two estuaries along the Italian Adriatic coast. Vibrio alginolyticus was the predominant species, followed by Vibrio parahaemolyticus, non-O1 Vibrio cholerae, and Vibrio vulnificus. By using a biochemical fingerprinting method, all isolates were grouped into nine phenotypes with similarity levels of 75 to 97.5%. The production of toxins capable of causing cytoskeleton-dependent changes was detected in a large number of Vibrio strains. These findings indicate a significant presence of potentially pathogenic Vibrio strains along the Adriatic coast.  相似文献   

19.
In the present study, thirteen genes involved in the reverse cholesterol transport (RCT) pathway were investigated for their associations with three fat depositions, eight fatty acid compositions and two growth-related phenotypes in a Wagyu x Limousin reference population, including 6 F(1) bulls, 113 F(1) dams, and 246 F(2) progeny. A total of 37 amplicons were used to screen single nucleotide polymorphisms (SNPs) on 6 F(1) bulls. Among 36 SNPs detected in 11 of these 13 genes, 19 were selected for genotyping by the Sequenom assay design on all F(2) progeny. Single-marker analysis revealed seven SNPs in ATP binding cassette A1, apolipoproteins A1, B and E, phospholipid transfer protein and paraoxinase 1 genes significantly associated with nine phenotypes (P<0.05). Previously, we reported genetic networks associated with 19 complex phenotypes based on a total of 138 genetic polymorphisms derived from 71 known functional genes. Therefore, after Bonferroni correction, these significant (adjusted P<0.05) and suggestive (adjusted P<0.10) associations were then used to identify genetic networks related to the RCT pathway. Multiple-marker analysis suggested possible genetic networks involving the RCT pathway for kidney-pelvic-heart fat percentage, rib-eye area, and subcutaneous fat depth phenotypes with markers derived from paraoxinase 1, apolipoproteins A1 and E, respectively. The present study confirmed that genes involved in cholesterol homeostasis are useful targets for investigating obesity in humans as well as for improving meat quality phenotypes in a livestock production.  相似文献   

20.
In a diverse array of avian and mammalian species, experimental manipulations of clutch size have tested the hypothesis that natural selection should adjust numbers of neonates produced so as to maximize the number of viable offspring at the end of the period of parental care. Reptiles have not been studied in this respect, probably because they rarely display parental care. However, females of all python species brood their eggs until hatching, but they do not care for their neonates. This feature provides a straightforward way to experimentally increase or reduce clutch size to see whether the mean clutch size observed in nature does indeed maximize hatching success and/or optimize offspring phenotypes. Eggs were removed or added to newly laid clutches of Ball Pythons ( Python regius ) in tropical Africa (nine control clutches, eight with 50% more eggs added, six with 42% of eggs removed). All clutches were brooded by females throughout the 2-month incubation period. Experimental manipulation of clutch-size did not significantly affect the phenotypes (morphology, locomotor ability) of hatchlings, but eggs in 'enlarged' clutches hatched later, and embryos were more likely to die before hatching. This mortality was due to desiccation of the eggs, with females being unable to cover 'enlarged' clutches sufficiently to retard water loss. Our results support the notion of an optimal clutch size, driven by limitations on parental ability to care for the offspring. However, the proximate mechanisms that generate this optimum value differ from those previously described in other kinds of animals. © 2003 The Linnean Society of London . Biological Journal of the Linnean Society 2003, 78 , 263–272.  相似文献   

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