RESUMO
This article explores the magnifying lenses of the COVID-19 syndemic to highlight how people racialized as migrants and refugees have been-and continue to be-disproportionally harmed. We use empirical evidence collected in our scholarly/activist work in Europe, Africa, South Asia, and the United States to examine migrant injustice as being produced by a combination of power structures and relations working to maintain colonial global orders and inequalities. This is what has been defined as "border imperialism." Our data, complemented by evidence from transnational solidarity groups, show that border imperialism has further intersected with the hygienic-sanitary logics of social control at play during the COVID-19 period. This intersection has resulted in increasingly coercive methods of restraining people on the move, as well as in increased-and new-forms of degradation of their lives, that is, an overall multiplication of border violences. At the same time, however, COVID-19 has provided a unique opportunity for grassroot solidarity initiatives and resistance led by people on the move to be amplified and extended. We conclude by emphasizing the need for community psychologists to take a more vigorous stance against oppressive border imperialist regimes and the related forms of violence they re/enact.
Assuntos
COVID-19 , Migrantes , Humanos , Sindemia , Violência , Justiça SocialRESUMO
A new study uses Chlamydomonas reinhardtii to understand how cell size homeostasis emerges from stochastic individual cell behaviors within a population. The authors find that a simple power law model was a poor predictor of cell size regulation; rather, it is better explained by a modified threshold model.
Assuntos
Chlamydomonas reinhardtii , Chlamydomonas reinhardtii/fisiologia , Tamanho Celular , HomeostaseRESUMO
BACKGROUND: Collective cell migration underlies many essential processes, including sculpting organs during embryogenesis, wound healing in the adult, and metastasis of cancer cells. At mid-oogenesis, Drosophila border cells undergo collective migration. Border cells round up into a small group at the pre-migration stage, detach from the epithelium and undergo a dynamic and highly regulated migration at the mid-migration stage, and stop at the oocyte, their final destination, at the post-migration stage. While specific genes that promote cell signaling, polarization of the cluster, formation of protrusions, and cell-cell adhesion are known to regulate border cell migration, there may be additional genes that promote these distinct active phases of border cell migration. Therefore, we sought to identify genes whose expression patterns changed during border cell migration. RESULTS: We performed RNA-sequencing on border cells isolated at pre-, mid-, and post-migration stages. We report that 1,729 transcripts, in nine co-expression gene clusters, are temporally and differentially expressed across the three migration stages. Gene ontology analyses and constructed protein-protein interaction networks identified genes expected to function in collective migration, such as regulators of the cytoskeleton, adhesion, and tissue morphogenesis, but also uncovered a notable enrichment of genes involved in immune signaling, ribosome biogenesis, and stress responses. Finally, we validated the in vivo expression and function of a subset of identified genes in border cells. CONCLUSIONS: Overall, our results identified differentially and temporally expressed genetic networks that may facilitate the efficient development and migration of border cells. The genes identified here represent a wealth of new candidates to investigate the molecular nature of dynamic collective cell migrations in developing tissues.
Assuntos
Proteínas de Drosophila , Drosophila , Animais , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Redes Reguladoras de Genes , Oogênese/genética , Movimento Celular/genética , Perfilação da Expressão Gênica , Drosophila melanogaster/genéticaRESUMO
Multicellular evolution is a major transition associated with momentous diversification of multiple lineages and increased developmental complexity. The volvocine algae comprise a valuable system for the study of this transition, as they span from unicellular to undifferentiated and differentiated multicellular morphologies despite their genomes being similar, suggesting multicellular evolution requires few genetic changes to undergo dramatic shifts in developmental complexity. Here, the evolutionary dynamics of six volvocine genomes were examined, where a gradual loss of genes was observed in parallel to the co-option of a few key genes. Protein complexes in the six species exhibited novel interactions, suggesting that gene loss could play a role in evolutionary novelty. This finding was supported by gene network modeling, where gene loss outpaces gene gain in generating novel stable network states. These results suggest gene loss, in addition to gene gain and co-option, may be important for the evolution developmental complexity.
Assuntos
Evolução Biológica , FilogeniaRESUMO
Background: The aim of this research was to examine the psychometrics of a short form version of the multidimensional Involvement in Alcoholics Anonymous scale (IAA-SF) by assessing the factor structure, internal consistency, and predictive validity. While there are several existing measures of involvement in Alcoholics Anonymous, many are either unidimensional or are limited in their ability to gather variation in the level of involvement in the different dimensions of 12-step programs. Objective: To achieve our aim, we used exploratory and principal axis factor analysis, correlation, and logistic regression with two unique and diverse samples. Longitudinal data were collected from a northern Illinois sample of 110 post-treatment adults, and cross-sectional data were from a random sample of 296 recovery home residents in the United States. Results: Results from the first sample suggested three exploratory factors (Principles Involvement, Social Involvement, and Spiritual Involvement) that were concordant with the proposed conceptualization and were then confirmed in the second sample. A 2nd order factor of global involvement was also found. All subscales demonstrated good to excellent internal consistency and were moderately associated with AA affiliation. Global and social involvement predicted greater odds of abstinence 2 years later, but principles and spiritual involvement did not. Conclusion: Overall results suggest the IAA- SF is a valid and reliable 12-item instrument for assessing involvement in the AA program, and the differential prediction suggests potential utility for a multidimensional approach to 12-step involvement.
Assuntos
Alcoólicos Anônimos , Alcoolismo , Adulto , Humanos , Estados Unidos , Alcoolismo/diagnóstico , Estudos Transversais , Psicometria , Reprodutibilidade dos TestesRESUMO
INTRODUCTION: The human papillomavirus (HPV) causes largely preventable cancers by completing a vaccination series. However, pediatric HPV vaccination rates remain low. Current evidence indicates that integrating five factors creates a high-quality recommendation associated with higher HPV vaccination rates. This quality improvement project aimed to evaluate the impact of an educational intervention to improve the quality of providers' recommendations and subsequent vaccination rates. METHOD: Using the Squire 2.0 Guidelines, clinical staff were observed during well-child visits (aged 11-12 years) before and after the intervention across three Plan-Do-Study-Act cycles. RESULTS: Thirty-nine encounters with mostly (n = 31; 80%) families of color. The quality of vaccine recommendations was improved after the intervention; however, vaccination rates did not increase for the 39 patients. Providers' delivery approach (presumptive vs. conversational) did increase vaccination rates. DISCUSSION: Providers' delivery style appears to be important when making HPV vaccine recommendations.
RESUMO
The evolution of multicellularity is a major evolutionary transition that underlies the radiation of many species in all domains of life, especially in eukaryotes. The volvocine green algae are an unconventional model system that holds great promise in the field given its genetic tractability, late transition to multicellularity, and phenotypic diversity. Multiple efforts at linking multicellularity-related developmental landmarks to key molecular changes, especially at the genome level, have provided key insights into the molecular innovations or lack thereof that underlie multicellularity. Twelve developmental changes have been proposed to explain the evolution of complex differentiated multicellularity in the volvocine algae. Co-option of key genes, such as cell cycle and developmental regulators has been observed, but with few exceptions, known co-option events do not seem to coincide with most developmental features observed in multicellular volvocines. The apparent lack of "master multicellularity genes" combined with no apparent correlation between gene gains for developmental processes suggest the possibility that many multicellular traits might be the product gene-regulatory and functional innovations; in other words, multicellularity can arise from shared genomic repertoires that undergo regulatory and functional overhauls.
RESUMO
The evolution of germ-soma cellular differentiation represents a key step in the evolution of multicellular individuality. Volvox carteri and its relatives, the volvocine green algae, provide a model system for studying the evolution of cellular differentiation. In V. carteri, the regA gene controls somatic cell differentiation and is found in a group of paralogs called the reg cluster, along with rlsA, rlsB, and rlsC. However, the developmental program of V. carteri is derived compared to other volvocine algae. Here we examine Volvox powersii which possesses an ancestral developmental program and independent evolution of the Volvox body plan. We sequenced the reg cluster from V. powersii wild-type and a mutant with fewer cells and altered germ-soma ratio. We found that the mutant strain's rlsB gene has a deletion predicted to cause a truncated protein product. We developed a genetic transformation procedure to insert wild-type rlsB into the mutant strain. Transformation did not result in phenotypic rescue, suggesting the rlsB mutation is insufficient for generating the mutant phenotype. The transformation techniques and sequences described here provide essential tools to study V. powersii, a species well suited for studying the evolution of cellular differentiation and convergent evolution of Volvox morphology.
Assuntos
Clorófitas , Volvox , Sequência de Bases , Diferenciação Celular , Volvox/genéticaRESUMO
Efficient, more accurate reporting of maize (Zea mays L.) phenology, crop condition, and progress is crucial for agronomists and policy makers. Integration of satellite imagery with machine learning models has shown great potential to improve crop classification and facilitate in-season phenological reports. However, crop phenology classification precision must be substantially improved to transform data into actionable management decisions for farmers and agronomists. An integrated approach utilizing ground truth field data for maize crop phenology (2013-2018 seasons), satellite imagery (Landsat 8), and weather data was explored with the following objectives: (i) model training and validation-identify the best combination of spectral bands, vegetation indices (VIs), weather parameters, geolocation, and ground truth data, resulting in a model with the highest accuracy across years at each season segment (step one) and (ii) model testing-post-selection model performance evaluation for each phenology class with unseen data (hold-out cross-validation) (step two). The best model performance for classifying maize phenology was documented when VIs (NDVI, EVI, GCVI, NDWI, GVMI) and vapor pressure deficit (VPD) were used as input variables. This study supports the integration of field ground truth, satellite imagery, and weather data to classify maize crop phenology, thereby facilitating foundational decision making and agricultural interventions for the different members of the agricultural chain.
RESUMO
In 2018, in response to increasingly oppressive and widespread federal immigration enforcement actions in the United States (U.S.) and around the globe - including family separation, immigration raids, detention, deportation of people who have lived in the country for much of their lives - the Society for Community Research & Action produced a statement on the effects of deportation and forced separation on immigrants, their families, and communities (SCRA, 2018). The statement focused exclusively on the impacts of deportation and forced family separation, documenting the damage done by oppressive U.S. policies and practices. We felt it was imperative to document this harm, and yet were uncomfortable producing a narrow paper that focused solely on harm. There are multiple ways immigrants and their allies resist deportation and other forms of oppression. This resistance is done individually, collectively, and in settings that vary in size and scope, including community-based, faith-based, direct care, and educational settings, as well as entire municipalities and transnational organizing settings. Settings facilitate resistance in many ways, focusing on those who are oppressed, their oppressors, and systems of oppression. In this statement, we describe the unique and overlapping ways in which settings facilitate resistance. We situate this review of the scientific and practice literature in the frameworks of change through social settings, empowering settings, healing justice, and decolonization. We also document recommendations for continued resistance.
Assuntos
Emigrantes e Imigrantes , Transtornos Mentais , Emigração e Imigração , Humanos , Políticas , Sociedades Científicas , Estados UnidosRESUMO
Malaria continues to be a major global health problem, where disease transmission is deeply linked to the repeated blood feeding nature of the anautogenous mosquito. Given the tight link between blood feeding and disease transmission, understanding basic biology behind mosquito physiology is a requirement for developing effective vector-borne disease control strategies. In the mosquito, numerous loss of function studies with notable phenotypes demonstrate microRNAs (miRNAs) play significant roles in mosquito physiology. While the field appreciates the importance of a handful of miRNAs, we still need global mosquito tissue miRNA transcriptome studies. To address this need, our goal was to determine the miRNA transcriptome for multiple tissues of the pre-vitellogenic mosquito. To this end, by using small RNA-Seq analysis, we determined miRNA transcriptomes in tissues critical for mosquito reproduction and immunity including (i) fat body-abdominal wall enriched tissues, (ii) midguts, (iii) ovaries, and (iv) remaining tissues comprised of the head and thorax. We found numerous examples of miRNAs exhibiting pan-tissue high- or low- expression, tissue exclusion, and tissue enrichment. We also updated and consolidated the miRNA catalog and provided a detailed genome architecture map for the malaria vector, Anopheles gambiae This study aims to build a foundation for future research on how miRNAs and potentially other small RNAs regulate mosquito physiology as it relates to vector-borne disease transmission.
Assuntos
Anopheles/genética , Perfilação da Expressão Gênica , MicroRNAs/genética , Mosquitos Vetores/genética , Análise de Sequência de RNA , Transcriptoma , Animais , Regulação da Expressão Gênica , Malária/parasitologia , Malária/transmissão , Especificidade de ÓrgãosAssuntos
Ecologia/métodos , Meio Ambiente , Genoma/genética , Genômica/métodos , Animais , Interação Gene-Ambiente , Genótipo , FenótipoRESUMO
Multicellularity is the premier example of a major evolutionary transition in individuality and was a foundational event in the evolution of macroscopic biodiversity. The volvocine chlorophyte lineage is well suited for studying this process. Extant members span unicellular, simple colonial, and obligate multicellular taxa with germ-soma differentiation. Here, we report the nuclear genome sequence of one of the most morphologically simple organisms in this lineage-the 4-celled colonial Tetrabaena socialis and compare this to the three other complete volvocine nuclear genomes. Using conservative estimates of gene family expansions a minimal set of expanded gene families was identified that associate with the origin of multicellularity. These families are rich in genes related to developmental processes. A subset of these families is lineage specific, which suggests that at a genomic level the evolution of multicellularity also includes lineage-specific molecular developments. Multiple points of evidence associate modifications to the ubiquitin proteasomal pathway (UPP) with the beginning of coloniality. Genes undergoing positive or accelerating selection in the multicellular volvocines were found to be enriched in components of the UPP and gene families gained at the origin of multicellularity include components of the UPP. A defining feature of colonial/multicellular life cycles is the genetic control of cell number. The genomic data presented here, which includes diversification of cell cycle genes and modifications to the UPP, align the genetic components with the evolution of this trait.
Assuntos
Evolução Biológica , Clorófitas/genética , Genes cdc , Componentes Genômicos , Ciclinas/genética , Genes do Retinoblastoma , Família Multigênica , Complexo de Endopeptidases do Proteassoma/genética , Seleção Genética , Transcriptoma , Ubiquitina/genéticaRESUMO
Losses of floral pigmentation represent one of the most common evolutionary transitions in flower color, yet the genetic basis for these changes has been elucidated in only a handful of cases. Here we used crossing studies, bulk-segregant RNA sequencing, phylogenetic analyses and functional tests to identify the gene(s) responsible for the transition to white flowers in Iochroma loxense. Crosses between I. loxense and its blue-flowered sister species, I. cyaneum, suggested that a single locus controls the flower color difference and that the white allele causes a nearly complete loss of pigmentation. Examining sequence variation across phenotypic pools from the crosses, we found that alleles at a novel R3 MYB transcription factor were tightly associated with flower color variation. This gene, which we term MYBL1, falls into a class of MYB transcriptional repressors and, accordingly, higher expression of this gene is associated with downregulation of multiple anthocyanin pigment pathway genes. We confirmed the repressive function of MYBL1 through stable transformation of Nicotiana. The mechanism underlying the evolution of white flowers in I. loxense differs from that uncovered in previous studies, pointing to multiple mechanisms for achieving fixed transitions in flower color intensity.
Assuntos
Flores/fisiologia , Pigmentação , Proteínas de Plantas/metabolismo , Proteínas Repressoras/metabolismo , Solanaceae/fisiologia , Sequência de Aminoácidos , Antocianinas/metabolismo , Teorema de Bayes , Segregação de Cromossomos/genética , Cruzamentos Genéticos , Flores/genética , Regulação da Expressão Gênica de Plantas , Loci Gênicos , Modelos Biológicos , Fenótipo , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas Repressoras/química , Proteínas Repressoras/genética , Solanaceae/genética , Nicotiana/metabolismoRESUMO
Porphyra umbilicalis (laver) belongs to an ancient group of red algae (Bangiophyceae), is harvested for human food, and thrives in the harsh conditions of the upper intertidal zone. Here we present the 87.7-Mbp haploid Porphyra genome (65.8% G + C content, 13,125 gene loci) and elucidate traits that inform our understanding of the biology of red algae as one of the few multicellular eukaryotic lineages. Novel features of the Porphyra genome shared by other red algae relate to the cytoskeleton, calcium signaling, the cell cycle, and stress-tolerance mechanisms including photoprotection. Cytoskeletal motor proteins in Porphyra are restricted to a small set of kinesins that appear to be the only universal cytoskeletal motors within the red algae. Dynein motors are absent, and most red algae, including Porphyra, lack myosin. This surprisingly minimal cytoskeleton offers a potential explanation for why red algal cells and multicellular structures are more limited in size than in most multicellular lineages. Additional discoveries further relating to the stress tolerance of bangiophytes include ancestral enzymes for sulfation of the hydrophilic galactan-rich cell wall, evidence for mannan synthesis that originated before the divergence of green and red algae, and a high capacity for nutrient uptake. Our analyses provide a comprehensive understanding of the red algae, which are both commercially important and have played a major role in the evolution of other algal groups through secondary endosymbioses.
Assuntos
Citoesqueleto/genética , Evolução Molecular , Genoma de Planta/genética , Porphyra/citologia , Porphyra/genética , Actinas/genética , Sinalização do Cálcio/genética , Ciclo Celular/genética , Parede Celular/genética , Parede Celular/metabolismo , Cromatina/genética , Cinesinas/genética , FilogeniaRESUMO
Despite its major impact on the evolution of Life on Earth, the transition to multicellularity remains poorly understood, especially in terms of its genetic basis. The volvocine algae are a group of closely related species that range in morphology from unicellular individuals (Chlamydomonas) to undifferentiated multicellular forms (Gonium) and complex organisms with distinct developmental programs and one (Pleodorina) or two (Volvox) specialized cell types. Modern genetic approaches, complemented by the recent sequencing of genomes from several key species, revealed that co-option of existing genes and pathways is the primary driving force for the evolution of multicellularity in this lineage. The initial transition to undifferentiated multicellularity, as typified by the extant Gonium, was driven primarily by the co-option of cell cycle regulation. Further morphological and developmental innovations in the lineage leading to Volvox resulted from additional co-option events involving genes important for embryonic inversion, asymmetric cell division, somatic and germ cell differentiation and the structure and function of the extracellular matrix. Because of their relatively low but variable levels of morphological and developmental complexity, simple underlying genetics and recent evolutionary history, the volvocine algae are providing significant insight into our understanding of the genetics and evolution of major developmental and morphological traits.
Assuntos
Diferenciação Celular/genética , Clorófitas/genética , Evolução Molecular , Filogenia , Chlamydomonas/classificação , Chlamydomonas/genética , Chlamydomonas/crescimento & desenvolvimento , Clorófitas/classificação , Clorófitas/crescimento & desenvolvimento , Células Germinativas/crescimento & desenvolvimento , Volvox/classificação , Volvox/genética , Volvox/crescimento & desenvolvimentoRESUMO
MYB transcription factors play an important role in regulating key plant developmental processes involving defense, cell shape, pigmentation, and root formation. Within this gene family, sequences containing an R2R3 MYB domain are the most abundant type and exhibit a wide diversity of functions. In this study, we identify 559 R2R3 MYB genes using whole genome data from four species of Solanaceae and reconstruct their evolutionary relationships. We compare the Solanaceae R2R3 MYBs to the well-characterized Arabidopsis thaliana sequences to estimate functional diversity and to identify gains and losses of MYB clades in the Solanaceae. We identify numerous R2R3 MYBs that do not appear closely related to Arabidopsis MYBs, and thus may represent clades of genes that have been lost along the Arabidopsis lineage or gained after the divergence of Rosid and Asterid lineages. Despite differences in the distribution of R2R3 MYBs across functional subgroups and species, the overall size of the R2R3 subfamily has changed relatively little over the roughly 50 million-year history of Solanaceae. We added our information regarding R2R3 MYBs in Solanaceae to other data and performed a meta-analysis to trace the evolution of subfamily size across land plants. The results reveal many shifts in the number of R2R3 genes, including a 54 % increase along the angiosperm stem lineage. The variation in R2R3 subfamily size across land plants is weakly positively correlated with genome size and strongly positively correlated with total number of genes. The retention of such a large number of R2R3 copies over long evolutionary time periods suggests that they have acquired new functions and been maintained by selection. Discovering the nature of this functional diversity will require integrating forward and reverse genetic approaches on an -omics scale.
Assuntos
Solanum lycopersicum/genética , Fatores de Transcrição/genética , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Sequência Conservada , Evolução Molecular , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Família Multigênica , Filogenia , Proteínas de Plantas/genética , Fatores de Transcrição/metabolismoRESUMO
Biochemical analysis of proteins relies on accurate quantification of protein concentration. Detailed in this appendix are some commonly used methods for protein analysis, e.g., Lowry, Bradford, bicinchoninic acid (BCA), UV spectroscopic, and 3-(4-carboxybenzoyl)quinoline-2-carboxaldehyde (CBQCA) assays. The primary focus of this report is assay selection, emphasizing sample and buffer compatibility. The fundamentals of generating protein assay standard curves and of data processing are considered, as are high-throughput adaptations of the more commonly used protein assays. Also included is a rapid, inexpensive, and reliable BCA assay of total protein in SDS-PAGE sample buffer that is used for equal loading of SDS-PAGE gels. © 2016 by John Wiley & Sons, Inc.
Assuntos
Proteínas/análise , Eletroforese em Gel de Poliacrilamida/métodos , Espectrofotometria/métodosRESUMO
The transition to multicellularity has occurred numerous times in all domains of life, yet its initial steps are poorly understood. The volvocine green algae are a tractable system for understanding the genetic basis of multicellularity including the initial formation of cooperative cell groups. Here we report the genome sequence of the undifferentiated colonial alga, Gonium pectorale, where group formation evolved by co-option of the retinoblastoma cell cycle regulatory pathway. Significantly, expression of the Gonium retinoblastoma cell cycle regulator in unicellular Chlamydomonas causes it to become colonial. The presence of these changes in undifferentiated Gonium indicates extensive group-level adaptation during the initial step in the evolution of multicellularity. These results emphasize an early and formative step in the evolution of multicellularity, the evolution of cell cycle regulation, one that may shed light on the evolutionary history of other multicellular innovations and evolutionary transitions.
Assuntos
Pontos de Checagem do Ciclo Celular/genética , Chlamydomonas/genética , Clorófitas/genética , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Evolução Biológica , Chlamydomonas/citologia , Clorófitas/classificação , Clorófitas/citologia , Tamanho do Genoma , Filogenia , Células Vegetais/metabolismo , Plasmídeos/química , Plasmídeos/metabolismo , Proteína do Retinoblastoma/genética , Proteína do Retinoblastoma/metabolismo , Transformação GenéticaRESUMO
Proliferating cells actively control their size by mechanisms that are poorly understood. The unicellular green alga Chlamydomonas reinhardtii divides by multiple fission, wherein a 'counting' mechanism couples mother cell-size to cell division number allowing production of uniform-sized daughters. We identified a sizer protein, CDKG1, that acts through the retinoblastoma (RB) tumor suppressor pathway as a D-cyclin-dependent RB kinase to regulate mitotic counting. Loss of CDKG1 leads to fewer mitotic divisions and large daughters, while mis-expression of CDKG1 causes supernumerous mitotic divisions and small daughters. The concentration of nuclear-localized CDKG1 in pre-mitotic cells is set by mother cell size, and its progressive dilution and degradation with each round of cell division may provide a link between mother cell-size and mitotic division number. Cell-size-dependent accumulation of limiting cell cycle regulators such as CDKG1 is a potentially general mechanism for size control.