117 research outputs found
Genetic structure of rainbow trout Oncorhynchus mykiss (Salmoniformes, Salmonidae) from aquaculture by DNA-markers
The rational use of valuable fish species from aquaculture is difficult to implement without knowledge of the state of the genetic structure of local stocks. Different types of DNA markers can be used to achieve the goals of selection and breeding work. The genetic structure of a local stock of rainbow trout (Oncorhynchus mykiss Walbaum, 1792) (Salmoniformes, Salmonidae) farmed in Ukraine was studied using DNA-markers: microsatellite (SSR-markers β simple-sequence repeats-markers) and intermicrosatellite (ISSR β inter-simple sequence repeat). Five fragments of trinucleotide microsatellite motifs with a single anchor nucleotide at the 3'-end were used as a primer for analysis by the ISSR-PCR method. Totally, 85 amplicons were obtained across the five loci, of which 92.9% were polymorphic. The total number of alleles ranged from 10 (marker (ACC)βG) to 23 (marker (AGC)βG). The following monomorphic amplicons were determined for the studied local stock of rainbow trout: according to marker (CTC)βC β 770 and 520 bp bands, for the marker (GAG)βC β 345, 295 and 260 bp, and for the marker (AGC)βC β 350 bp. The average number of polymorphic bands per locus was 15.8. The selected ISSR primers had a level of polymorphic information content above the average. The most effective markers for molecular-genetic analysis of rainbow trout were (AGC)βG and (AGC)βC according to the percentage of polymorphic bands, marker index, effective multiplex ratio and resolving power. The selected ISSR loci allow the genetic structure of the studied local stock to be characterized using the total and the effective number of alleles per locus (Na and Ne were 1.9 and 1.4, respectively), the Shannon index (average value I was 0.4) and the unbiased expected heterozygosity (mean uHe = 0.3). Microsatellite-based analysis showed features of the genetic structure of the local stock of rainbow trout at six microsatellite loci (OMM 1032, OMM 1077, OMM 1088, Str 15, Str 60, Str 73). Allelic diversity was established and alleles with the highest frequency and most typical for the given stock were identified. The Shannon index and unbiased expected heterozygosity were determined using SSR-markers and were 1.42 and 0.79, respectively. This depicts the complexity of the population structure, a high level of genetic diversity and indicates a high level of heterozygosity of local stock. The βgene pool profileβ established as a result of ISSR-PCR in the future will help to differentiate local stocks of rainbow trout in aquaculture of Ukraine. Microsatellite markers provide the ability to determine individual features of genetic variation of local populations and to conduct the management of genetic resources on fish farms
Oncogenic PIK3CA corrupts growth factor signaling specificity
Pathological activation of the PI3K/AKT pathway is among the most frequent defects in human cancer and is also the cause of rare overgrowth disorders. Yet, there is currently no systematic understanding of the quantitative flow of information within PI3K/AKT signaling and how it is perturbed by disease-causing mutations. Here, we develop scalable, single-cell approaches for systematic analyses of signal processing within the PI3K pathway, enabling precise calculations of its information transfer for different growth factors. Using genetically-engineered human cell models with allele dose-dependent expression of PIK3CAH1047R, we show that this oncogene is not a simple, constitutive pathway activator but a context-dependent modulator of extracellular signal transfer. PIK3CAH1047Rreduces information transmission downstream of IGF1 while selectively enhancing EGF-induced signaling and transcriptional responses. This leads to a gross reduction in signaling specificity, akin to βblurredβ signal perception. The associated increase in signaling heterogeneity promotes phenotypic diversity in a human cervical cancer cell line model and in human induced pluripotent stem cells. Collectively, these findings and the accompanying methodological advances lay the foundations for a systematic mapping of the quantitative mechanisms of PI3K/AKT-dependent signal processing and phenotypic control in health and disease
Socioeconomic development, family income, and psychosocial risk factors: a study of families with children in public elementary school
The role of metacognition in self-critical rumination: an investigation in individuals presenting with low self-esteem
Background: No research, to date, has directly investigated the role of metacognition in self-critical rumination and low self-esteem. Aim: To investigate the presence of metacognitive beliefs about self-critical rumination; the goal of self-critical rumination and its stop signal; and the degree of detachment from intrusive self-critical thoughts. Method: Ten individuals reporting both a self-acknowledged tendency to judge themselves critically and having low self-esteem were assessed using metacognitive profiling, a semi-structured interview. Results: All participants endorsed both positive and negative metacognitive beliefs about self-critical rumination. Positive metacognitive beliefs concerned the usefulness of self-critical rumination as a means of improving cognitive performance and enhancing motivation. Negative metacognitive beliefs concerned the uncontrollability of self-critical rumination and its negative impact on mood, motivation and perception of self-worth. The primary goal of engaging in self-critical rumination was to achieve a better or clearer understanding of a given trigger situation or to feel more motivated to resolve it. However, only four participants were able to identify when this goal had been achieved, which was if the trigger situation were not to occur again. Participants unanimously stated that they were either unable to detach from their self-critical thoughts or could do so some of the time with varying degrees of success. More often than not, though, self-critical thoughts were viewed as facts, would rarely be seen as distorted or biased, and could take hours or days to dissipate. Conclusions: These findings provide preliminary evidence that specific facets of metacognition play a role in the escalation and perseveration of self-critical rumination
Angiotensin-converting enzyme inhibitors of Bothrops jararaca snake venom affect the structure of mice seminiferous epithelium
A genome-wide identification and comparative analysis of the lentil MLO genes
Revista electrΓ³nica on linePowdery mildew is a widespread fungal plant disease that can cause significant losses in
many crops. Some MLO genes (Mildew resistance locus O) have proved to confer a durable
resistance to powdery mildew in several species. Resistance granted by the MLO gene family
members has prompted an increasing interest in characterizing these genes and implementing
their use in plant breeding. Lentil (Lens culinaris Medik.) is a widely grown food
legume almost exclusively consumed as dry seed with an average world production of 4.5
million tons. Powdery mildew causes severe losses on certain lentil cultivars under particular
environmental conditions. Data mining of the lentil CDC Redberry draft genome allowed to
identify up to 15 gene sequences with homology to known MLO genes, designated as
LcMLOs. Further characterization of these gene sequences and their deduced protein
sequences demonstrated conformity with key MLO protein characteristics such as the presence
of transmembrane and calmodulin binding domains, as well as that of other conserved
motifs. Phylogenetic and other comparative analyses revealed that LcMLO1 and LcMLO3
are the most likely gene orthologs related to powdery mildew response in other species,
sharing a high similarity with other known resistance genes of dicot species, such as pea
PsMLO1 and Medicago truncatula MtMLO1 and MtMLO3. Sets of primers were designed
as tools to PCR amplify the genomic sequences of LcMLO1 and LcMLO3, also to screen
lentil germplasm in search of resistance mutants. Primers were used to obtain the complete
sequences of these two genes in all of the six wild lentil relatives. Respective to each gene,
all Lens sequences shared a high similarity. Likewise, we used these primers to screen a
working collection of 58 cultivated and 23 wild lentil accessions in search of length polymorphisms
present in these two genes. All these data widen the insights on this gene family and
can be useful for breeding programs in lentil and close related species.S
Dynamics of notch pathway expression during mouse testis post-natal development and along the spermatogenic cycle
Articles in International JournalsThe transcription and expression patterns of Notch pathway components (Notch 1β3, Delta1 and 4, Jagged1) and effectors
(Hes1, Hes2, Hes5 and Nrarp) were evaluated (through RT-PCR and IHC) in the mouse testis at key moments of post-natal
development, and along the adult spermatogenic cycle. Notch pathway components and effectors are transcribed in the
testis and expressed in germ, Sertoli and Leydig cells, and each Notch component shows a specific cell-type and timewindow
expression pattern. This expression at key testis developmental events prompt for a role of Notch signaling in prepubertal
spermatogonia quiescence, onset of spermatogenesis, and regulation of the spermatogenic cycle
Spinal Cord Injury Causes Sustained Disruption of the Blood-Testis Barrier in the Rat
There is a high incidence of infertility in males following traumatic spinal cord injury (SCI). Quality of semen is frequently poor in these patients, but the pathophysiological mechanism(s) causing this are not known. Blood-testis barrier (BTB) integrity following SCI has not previously been examined. The objective of this study was to characterize the effects of spinal contusion injury on the BTB in the rat. 63 adult, male Sprague Dawley rats received SCI (nβ=β28), laminectomy only (nβ=β7) or served as uninjured, age-matched controls (nβ=β28). Using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), BTB permeability to the vascular contrast agent gadopentate dimeglumine (Gd) was assessed at either 72 hours-, or 10 months post-SCI. DCE-MRI data revealed that BTB permeability to Gd was greater than controls at both 72 h and 10 mo post-SCI. Histological evaluation of testis tissue showed increased BTB permeability to immunoglobulin G at both 72 hours- and 10 months post-SCI, compared to age-matched sham-operated and uninjured controls. Tight junctional integrity within the seminiferous epithelium was assessed; at 72 hours post-SCI, decreased expression of the tight junction protein occludin was observed. Presence of inflammation in the testes was also examined. High expression of the proinflammatory cytokine interleukin-1 beta was detected in testis tissue. CD68+ immune cell infiltrate and mast cells were also detected within the seminiferous epithelium of both acute and chronic SCI groups but not in controls. In addition, extensive germ cell apoptosis was observed at 72 h post-SCI. Based on these results, we conclude that SCI is followed by compromised BTB integrity by as early as 72 hours post-injury in rats and is accompanied by a substantial immune response within the testis. Furthermore, our results indicate that the BTB remains compromised and testis immune cell infiltration persists for months after the initial injury
Role of Ξ²-Catenin in Post-Meiotic Male Germ Cell Differentiation
Though roles of Ξ²-catenin signaling during testis development have been well established, relatively little is known about its role in postnatal testicular physiology. Even less is known about its role in post-meiotic germ cell development and differentiation. Here, we report that Ξ²-catenin is highly expressed in post-meiotic germ cells and plays an important role during spermiogenesis in mice. Spermatid-specific deletion of Ξ²-catenin resulted in significantly reduced sperm count, increased germ cell apoptosis and impaired fertility. In addition, ultrastructural studies show that the loss of Ξ²-catenin in post-meiotic germ cells led to acrosomal defects, anomalous release of immature spermatids and disruption of adherens junctions between Sertoli cells and elongating spermatids (apical ectoplasmic specialization; ES). These defects are likely due to altered expression of several genes reportedly involved in Sertoli cell-germ cell adhesion and germ cell differentiation, as revealed by gene expression analysis. Taken together, our results suggest that Ξ²-catenin is an important molecular link that integrates Sertoli cell-germ cell adhesion with the signaling events essential for post-meiotic germ cell development and maturation. Since Ξ²-catenin is also highly expressed in the Sertoli cells, we propose that binding of germ cell Ξ²-catenin complex to Ξ²-catenin complex on Sertoli cell at the apical ES surface triggers a signaling cascade that regulates post-meiotic germ cell differentiation
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