71 research outputs found
Identification and phylogenetic comparison of p53 in two distinct mussel species (Mytilus)
Author Posting. © The Authors, 2005. This is the author's version of the work. It is
posted here by permission of Elsevier B. V. for personal use, not for redistribution. The
definitive version was published in Comparative Biochemistry and Physiology Part C: Toxicology & Pharmacology 140 (2005): 237-250, doi:10.1016/j.cca.2005.02.011.The extent to which humans and wildlife are exposed to anthropogenic challenges is an important focus of environmental research. Potential use of p53 gene family marker(s) for aquatic environmental effects monitoring is the long-term goal of this research. The p53 gene is a tumor suppressor gene that is fundamental in cell cycle control and apoptosis. It is mutated or differentially expressed in about 50% of all human cancers and p53 family members are differentially expressed in leukemic clams. Here, we report the identification and characterization of the p53 gene in two species of Mytilus, Mytilus edulis and Mytilus trossulus, using RT-PCR with degenerate and specific primers to conserved regions of the gene. The Mytilus p53 proteins are 99.8% identical and closely related to clam (Mya) p53. In particular, the 3′ untranslated regions were examined to gain understanding of potential post-transcriptional regulatory pathways of p53 expression. We found nuclear and cytoplasmic polyadenylation elements, adenylate/uridylate-rich elements, and a K-box motif previously identified in other, unrelated genes. We also identified a new motif in the p53 3′UTR which is highly conserved across vertebrate and invertebrate species. Differences between the p53 genes of the two Mytilus species may be part of genetic determinants underlying variation in leukemia prevalence and/or development, but this requires further investigation. In conclusion, the conserved regions in these p53 paralogues may represent potential control points in gene expression. This information provides a critical first step in the evaluation of p53 expression as a potential marker for environmental assessment.AFM was supported by the Greater Vancouver Regional District, BC, Canada, and RLC was supported by STAR grant R82935901 from the Environmental Protection Agency (USA)
Modular and cultural factors in biological understanding: an experimental approach to the cognitive basis of science
What follows is a discussion of three sets of experimental results that deal with various aspects of universal biological understanding among American and Maya children and adults. The first set of experiments shows that by the age of four-to-five years (the earliest age tested in this regard) urban American and Yukatek Maya children employ a concept of innate species potential, or underlying essence, as an inferential framework for understanding the affiliation of an organism to a biological species, and for projecting known and unknown biological properties to organisms in the face of uncertainty. The second set of experiments shows that the youngest Maya children do not have an anthropocentric understanding of the biological world. Children do not initially need to reason about non-human living kinds by analogy to human kinds. The third set of results show that the same taxonomic rank is cognitively preferred for biological induction in two diverse populations: people raised in the Mid-western USA and Itza' Maya of the Lowland Meso-american rainforest. This is the generic species the level of oak and robin. These findings cannot be explained by domain-general models of similarity because such models cannot account for why both cultures prefer species-like groups in making inferences about the biological world, although Americans have relatively little actual knowledge or experience at this level. The implication from these experiments is that folk biology may well represent an evolutionary design: universal taxonomic structures, centred on essence-based generic species, are arguably routine products of our ‘habits of mind,' which may be in part naturally selected to grasp relevant and recurrent ‘habits of the world.' The science of biology is built upon these domain-specific cognitive universals: folk biology sets initial cognitive constraints on the development of any possible macro-biological theory, including the initial development of evolutionary theory. Nevertheless, the conditions of relevance under which science operates diverge from those pertinent to folk biology. For natural science, the motivating idea is to understand nature as it is ‘in itself,' independently of the human observer (as far as possible). From this standpoint, the species-concept, like taxonomy and teleology, may arguably be allowed to survive in science as a regulative principle that enables the mind to readily establish stable contact with the surrounding environment, rather than as an epistemic concept that guides the search for truth
Chromosomal-level assembly of the Asian Seabass genome using long sequence reads and multi-layered scaffolding
We report here the ~670 Mb genome assembly of the Asian seabass (Lates calcarifer), a tropical marine teleost. We used long-read sequencing augmented by transcriptomics, optical and genetic mapping along with shared synteny from closely related fish species to derive a chromosome-level assembly with a contig N50 size over 1 Mb and scaffold N50 size over 25 Mb that span ~90% of the genome. The population structure of L. calcarifer species complex was analyzed by re-sequencing 61 individuals representing various regions across the species' native range. SNP analyses identified high levels of genetic diversity and confirmed earlier indications of a population stratification comprising three clades with signs of admixture apparent in the South-East Asian population. The quality of the Asian seabass genome assembly far exceeds that of any other fish species, and will serve as a new standard for fish genomics
The Tetraodon nigroviridis reference transcriptome: Developmental transition, length retention and microsynteny of long non-coding RNAs in a compact vertebrate genome
Pufferfish such as fugu and tetraodon carry the smallest genomes among all vertebrates and are ideal for studying genome evolution. However, comparative genomics using these species is hindered by the poor annotation of their genomes. We performed RNA sequencing during key stages of maternal to zygotic transition of Tetraodon nigroviridis and report its first developmental transcriptome. We assembled 61,033 transcripts (23,837 loci) representing 80% of the annotated gene models and 3816 novel coding transcripts from 2667 loci. We demonstrate the similarities of gene expression profiles between pufferfish and zebrafish during maternal to zygotic transition and annotated 1120 long non-coding RNAs (lncRNAs) many of which differentially expressed during development. The promoters for 60% of the assembled transcripts result validated by CAGE-seq. Despite the extreme compaction of the tetraodon genome and the dramatic loss of transposons, the length of lncRNA exons remain comparable to that of other vertebrates and a small set of lncRNAs appears enriched for transposable elements suggesting a selective pressure acting on lncRNAs length and composition. Finally, a set of lncRNAs are microsyntenic between teleost and vertebrates, which indicates potential regulatory interactions between lncRNAs and their flanking coding genes. Our work provides a fundamental molecular resource for vertebrate comparative genomics and embryogenesis studies
Long-term, high frequency in situ measurements of intertidal mussel bed temperatures using biomimetic sensors
At a proximal level, the physiological impacts of global climate change on ectothermic organisms are manifest as changes in body temperatures. Especially for plants and animals exposed to direct solar radiation, body temperatures can be substantially different from air temperatures. We deployed biomimetic sensors that approximate the thermal characteristics of intertidal mussels at 71 sites worldwide, from 1998-present. Loggers recorded temperatures at 10-30 min intervals nearly continuously at multiple intertidal elevations. Comparisons against direct measurements of mussel tissue temperature indicated errors of similar to 2.0-2.5 degrees C, during daily fluctuations that often exceeded 15 degrees-20 degrees C. Geographic patterns in thermal stress based on biomimetic logger measurements were generally far more complex than anticipated based only on 'habitat-level' measurements of air or sea surface temperature. This unique data set provides an opportunity to link physiological measurements with spatially-and temporally-explicit field observations of body temperature
Genome-Wide Identification of Alternatively Spliced mRNA Targets of Specific RNA-Binding Proteins
BACKGROUND: Alternative splicing plays an important role in generating molecular and functional diversity in multi-cellular organisms. RNA binding proteins play crucial roles in modulating splice site choice. The majority of known binding sites for regulatory proteins are short, degenerate consensus sequences that occur frequently throughout the genome. This poses an important challenge to distinguish between functionally relevant sequences and a vast array of those occurring by chance. METHODOLOGY/PRINCIPAL FINDINGS: Here we have used a computational approach that combines a series of biological constraints to identify uridine-rich sequence motifs that are present within relevant biological contexts and thus are potential targets of the Drosophila master sex-switch protein Sex-lethal (SXL). This strategy led to the identification of one novel target. Moreover, our systematic analysis provides a starting point for the molecular and functional characterization of an additional target, which is dependent on SXL activity, either directly or indirectly, for regulation in a germline-specific manner. CONCLUSIONS/SIGNIFICANCE: This approach has successfully identified previously known, new, and potential SXL targets. Our analysis suggests that only a subset of potential SXL sites are regulated by SXL. Finally, this approach should be directly relevant to the large majority of splicing regulatory proteins for which bonafide targets are unknown
Cabotegravir for HIV Prevention in Cisgender Men and Transgender Women
Background: Safe and effective long-acting injectable agents for preexposure prophylaxis (PrEP) for human immunodeficiency virus (HIV) infection are needed to increase the options for preventing HIV infection. Methods: We conducted a randomized, double-blind, double-dummy, noninferiority trial to compare long-acting injectable cabotegravir (CAB-LA, an integrase strand-transfer inhibitor [INSTI]) at a dose of 600 mg, given intramuscularly every 8 weeks, with daily oral tenofovir disoproxil fumarate-emtricitabine (TDF-FTC) for the prevention of HIV infection in at-risk cisgender men who have sex with men (MSM) and in at-risk transgender women who have sex with men. Participants were randomly assigned (1:1) to receive one of the two regimens and were followed for 153 weeks. HIV testing and safety evaluations were performed. The primary end point was incident HIV infection. Results: The intention-to-treat population included 4566 participants who underwent randomization; 570 (12.5%) identified as transgender women, and the median age was 26 years (interquartile range, 22 to 32). The trial was stopped early for efficacy on review of the results of the first preplanned interim end-point analysis. Among 1698 participants from the United States, 845 (49.8%) identified as Black. Incident HIV infection occurred in 52 participants: 13 in the cabotegravir group (incidence, 0.41 per 100 person-years) and 39 in the TDF-FTC group (incidence, 1.22 per 100 person-years) (hazard ratio, 0.34; 95% confidence interval, 0.18 to 0.62). The effect was consistent across prespecified subgroups. Injection-site reactions were reported in 81.4% of the participants in the cabotegravir group and in 31.3% of those in the TDF-FTC group. In the participants in whom HIV infection was diagnosed after exposure to CAB-LA, INSTI resistance and delays in the detection of HIV infection were noted. No safety concerns were identified. Conclusions: CAB-LA was superior to daily oral TDF-FTC in preventing HIV infection among MSM and transgender women. Strategies are needed to prevent INSTI resistance in cases of CAB-LA PrEP failure
Clinical experience with moroctocog alfa (AF-CC) in younger paediatric patients with severe haemophilia A: Two open-label studies
WOS: 000442583600048PubMed ID: 29582525IntroductionThe pharmacokinetics (PK), efficacy and safety of moroctocog alfa (AF-CC) have been demonstrated in haemophilia A patients aged 6years. AimThese studies aimed to further describe moroctocog alfa (AF-CC) experience in paediatric patients (<12years) with severe haemophilia A (FVIII:C<1%). MethodsTwo prospective, open-label studies enrolled patients aged <12years: one study with 37 previously treated patients (PTPs) and another with 23 previously untreated patients (PUPs). All patients initially received 50IU/kg of moroctocog alfa (AF-CC) to evaluate either recovery alone, or with other PK parameters (6 to <12years) before continuing treatment for 100 exposure days (EDs) or 24months. ResultsAt baseline, mean (SD) recovery ranged between 1.32 +/- 0.65 (PUPs aged <2years) and 2.13 +/- 0.82 (PTPs aged 6 to <12years). The mean (+/- SD) half-life was 9.12 +/- 1.94hours in PTPs aged 6 to <12years. No new safety signals were detected in either study, 2 transient lower titre inhibitors occurred in PTPs while 8 inhibitors (3 low and 5 high titre) were detected in PUPs. Most bleeding episodes resolved with one infusion (94% [893/954]). The annualised bleeding rate (ABR) in the PTP study was 27.5 and 4.2 for patients reporting an on-demand and routine prophylaxis regimen at baseline, respectively. In the PUP study, the overall ABR was 5.9. ConclusionMoroctocog alfa (AF-CC) had expected PK findings (lower recovery in young children compared with older children) along with being safe and efficacious in a population of young severe haemophilia A patients.PfizerPfizerPfize
Clinical experience with moroctocog alfa (AF-CC) in younger paediatric patients with severe haemophilia A: Two open-label studies
- …