Circular and linear mitochondrial genomes in cytoplasmic male sterile maize [abstract]

Abstract only availableCytoplasmic male sterility (CMS) is a maternally inherited condition in which a plant has an inability to produce viable pollen. It is usually due to the production of a toxic chimeric protein within the mitochondria during the maturation of pollen grains. In maize (Zea mays), there are three types of CMS: CMS-T, CMS-C and CMS-S. The S-type of cytoplasmic male sterility (CMS-S) in maize is associated with the expression of a rearranged mitochondrial DNA region. This CMS-S-specific region includes two co-transcribed chimeric open reading frames, orf355 and orf77. The nuclear restorer-of-fertility gene, Rf3, cleaves all transcripts containing both orfs, including the CMS-S-specific linear 1.6 kb mRNA; this results in male fertility. The Lancaster Surecrop-derived inbred line A619 carries a different and weaker restorer called Rf9. Fertility restoration by Rf3 and Rf9 was compared for their effects upon the CMS-associated region of mitochondrial DNA. Unlike Rf3, Rf9 affects the organization of the CMS-S-specific region. It appears to do this by affecting recombination between linear "S" plasmids and the CMS-S-specific region of the main mitochondrial genome, which produces a linear end from which transcripts for the 1.6 kb mRNA are initiated. By reducing the amount of recombination, Rf9 reduces the amount of linear template available for transcribing the S-associated 1.6 kb RNA. A reduction in this transcript is associated with an increase in pollen survival. We have studied the effects of the two restorer-of-fertility genes from several different inbred lines on the amounts of integrated and linearized orf355/orf77 genes within CMS-S mtDNA.MU Monsanto Undergraduate Research Fellowshi

Anti-Transgender Policies and Practices in Social Work Education, Accreditation, and Licensing: A Call for Change

The social work profession is guided by the values of social justice and the dignity and worth of the person. The National Association of Social Workers (NASW) Code of Ethics requires that all social workers act in a professional manner consistent with these values. These values mandate that social workers “challenge social injustice on behalf of and in concert with vulnerable and oppressed individuals and groups.” Yet, historically, and contemporarily, the social work profession and national professional organizations (i.e., NASW, the Council on Social Work Education (CSWE), Associate of Social Work Boards (ASWB), Society for Social Work and Research (SSWR), and the American Academy of Social Work and Social Welfare (AASW) have failed to advocate for and work in solidarity with transgender and gender expansive (TGE) individuals and groups to advance social justice. This commentary will examine how the social work profession and its national professional organizations have not followed the NASW Code of Ethics as it relates to T E communities. Specifically, the article ill (1) unpack the ways in which explicit and implicit social work curriculum and standards in accredited US social work programs do little to equip students to effectively serve transgender clients and communities upon graduation, (2) discuss the lack of advocacy for and solidarity with TGE communities from professional social work organizations, and (3) review policies governing the licensure of social work practitioners related to culturally responsive social work practice with TGE clients and communities. This commentary provides a set of recommendations for countering and reducing transphobia in the social work profession in the areas education, practice, and policy. We conclude with a call for change for the social work profession that achieves the values of social justice and dignity and worth of TGE individuals, groups, and communities

Analysis of mitochondrial DNA insertions into a nuclear chromosome of the maize B73 line

Abstract only availableMitochondrial DNA (mtDNA) is known to have integrated into the nuclear DNA of plants and animals. The purpose of this project is to investigate the on-going migration of mtDNA into the nuclear DNA of maize plants. Specific objectives are to discover the amount of DNA incorporated, whether it is the whole mitochondrial genome or sections, and to see if it has replicated after migration. The maize inbred line B73 has a particularly large mt DNA insert on chromosome 9. Using the fluorescent in situ hybridization (FISH) method, the arrangement of inserted mitochondrial DNA was examined. The FISH method uses fluorescently labeled mtDNA as probes for hybridization to chromosomes. Regions of the chromosomes that contain mtDNA can then be detected using a compound microscope with fluorescent attachments. Locations that contain more mtDNA are brighter. Three combinations of probes that cover different parts of the mitochondrial genome were employed. In order to analyze the arrangement of the DNA, the chromosomes were prepared from a stage of meiosis called pachynema in which the chromosomes are elongated and have not yet begun to condense. The results have confirmed the presence of all three probes within the large insertion of mtDNA on chromosome 9 of B73. The data suggest that either different parts of the mitochondrial genome are incorporated preferentially or that there is selective replication of portions of the mitochondrial genome after incorporation.MU Monsanto Undergraduate Research Fellowshi

Identification of chloroplast DNA insertions in nuclear chromosomes of maize B73 line using the FISH procedure

Abstract only availableIt is known that chloroplast DNA can incorporate itself into the nuclear genome of plants. However, the sites of chloroplast (ct) DNA integration into chromosomes of maize have not yet been analyzed. This project is the first attempt to find the location of the ctDNA on the maize chromosomes. Fluorescent in situ hybridization is a technique that has proved useful in karyotyping and chromosomal mapping in maize. The FISH procedure is being used in this study to discover the location of the ctDNA in the nuclear genome of the inbred line B37. In order to develop ctDNA “probes” for FISH analysis, we have used the polymerase chain reaction (PCR) to produce fragments of ctDNA. Primers were chosen to amplify fragments of 10 kb or larger. The amplified DNAs were purified and labeled with fluorescent dyes and these probes were subsequently hybridized to chromosomes. The probes recognize and bind to the corresponding DNA sequences within the chromosomes. Root tip cells were used to prepare the slides for hybridization. Because the cells are collected during the metaphase stage of division, the chromosomes are compact and more easily visible. Chromosomes that contain ctDNA can be detected using a compound microscope with fluorescent attachments. The location of the ctDNA on the chromosomes is made visible by the fluorescent labeling of the probe. Eight of eleven regions of the chloroplast genome of the B73 line have been specifically amplified and have been observed under the microscope for FISH analysis. This information will contribute to an understanding of the extent and mechanism of transfer of organellar genomes to the nucleus.MU Monsanto Undergraduate Research Fellowshi

Identification of chloroplast DNA insertions in B73 nuclear chromosomes [abstract]

Abstract only availableIt is known that DNA from mitochondria and chloroplasts migrates to the nucleus and incorporates into the nuclear genome. It is unknown how often this transfer and integration process occurs or if specific sites in the chromosomes are preferred. We have evidence that chloroplast DNA has integrated into multiple sites within chromosomes in the B73 inbred line of maize. This has been shown with a procedure called FISH, Fluorescence in situ Hybridization, in which fluorescent probes created from DNA hybridize with chromosomes in places where there is a match. Probes for this project were generated from chloroplast DNA. The chloroplasts were separated by centrifugation and lysed to obtain the DNA. The chloroplast genome was subdivided into 15 regions. Pieces of chloroplast DNA corresponding to 14 of the 15 regions were amplified using PCR (the polymerase chain reaction). The amplified DNA was purified and labeled with fluorescent dyes to create probes. These probes were subsequently hybridized to metaphase chromosome spreads on slides. The probes recognized and bound to DNA sequences in the chromosomes. With the completion of the chloroplast DNA mapping, the B73 inbred maize line will have a complete diagram of the locations of major chloroplast DNA insertions.MU Monsanto Undergraduate Research Fellowshi

A multi-country test of brief reappraisal interventions on emotions during the COVID-19 pandemic.

The COVID-19 pandemic has increased negative emotions and decreased positive emotions globally. Left unchecked, these emotional changes might have a wide array of adverse impacts. To reduce negative emotions and increase positive emotions, we tested the effectiveness of reappraisal, an emotion-regulation strategy that modifies how one thinks about a situation. Participants from 87 countries and regions (n = 21,644) were randomly assigned to one of two brief reappraisal interventions (reconstrual or repurposing) or one of two control conditions (active or passive). Results revealed that both reappraisal interventions (vesus both control conditions) consistently reduced negative emotions and increased positive emotions across different measures. Reconstrual and repurposing interventions had similar effects. Importantly, planned exploratory analyses indicated that reappraisal interventions did not reduce intentions to practice preventive health behaviours. The findings demonstrate the viability of creating scalable, low-cost interventions for use around the world

Analysis of maize mitochondrial genome structures in vivo [abstract]

Abstract only availableFaculty Mentor: Dr. Kathleen Newton, Biological SciencesMitochondria are organelles containing their own genomic DNA that are found in most eukaryotic cells. In contrast to those of animals, plant mitochondrial genomes are large and very complex in structure. While maize mitochondrial DNA can be mapped as a large single circle, it has not been observed as such.  Thus, the in vivo organization of the mitochondrial genome is not known.  Using the B37 maize inbred line, which has a 570 kilobase (kb) mitochondrial genome, observations were made regarding the possibility of sub-genomes resulting from recombination between repeats.  Mitochondria were isolated from fresh B37 seedling shoots and were placed on slides to be observed using the FISH (Fluorescent in situ Hybridization) technique.  Two probes were used, cosmid 6 in Alexafluor 488 (green) and cosmid 19 in Texas Red (red).  These cosmids are separated in the mitochondrial genome by approximately 350kb.  They also occur on separate sides of a small repeat that is known to recombine frequently.  If the genome is intact the two colors should overlap and produce a yellow color.  If there are sub-genomes, red and green should be seen individually.  The mitochondria were observed on an Olympus Spectral Imaging Microscope and the genome appeared to be fragmented most of the time. Five slides were counted and 31,077 spots were observed.  The red: green: yellow ratio was 6.44 : 2.96 :1.00.  Stretching out of an intact mitochondrial genome could cause apparent sub-genomes.  However, it is more likely that there are sub-genomes present in separate mitochondria because small mitochondria (about one micron) were selected during the isolation procedure. This is small enough that the microscope should have seen the signal as overlapping.  Future studies could extend the analysis into other maize lines and to other types of plants to determine if the sub-genomic structures are universal

Reproducibility Project: Psychology

Reproducibility is a defining feature of science, but the extent to which it characterizes current research is unknown. We conducted replications of 100 experimental and correlational studies published in three psychology journals using high-powered designs and original materials when available

Data from: Estimating the reproducibility of psychological science

This record contains the underlying research data for the publication "Estimating the reproducibility of psychological science" and the full-text is available from: https://ink.library.smu.edu.sg/lkcsb_research/5257Reproducibility is a defining feature of science, but the extent to which it characterizes current research is unknown. We conducted replications of 100 experimental and correlational studies published in three psychology journals using high-powered designs and original materials when available. Replication effects were half the magnitude of original effects, representing a substantial decline. Ninety-seven percent of original studies had statistically significant results. Thirty-six percent of replications had statistically significant results; 47% of original effect sizes were in the 95% confidence interval of the replication effect size; 39% of effects were subjectively rated to have replicated the original result; and if no bias in original results is assumed, combining original and replication results left 68% with statistically significant effects. Correlational tests suggest that replication success was better predicted by the strength of original evidence than by characteristics of the original and replication teams