Biology subjects

Ward, N. J.

Publications and source records attributed to Ward, N. J..

3 recordsLinked to original sources

bioRxiv2023

From goal to outcome: analyzing the progression of biomedical sciences PhD careers in a longitudinal study using an expanded taxonomy

Biomedical sciences PhDs pursue a wide range of careers inside and outside academia. However, there is little data regarding how career interests of PhD students relate to the decision to pursue postdoctoral training or to their eventual career outcomes. Here, we present the career goals and career outcomes of 1,452 biomedical sciences PhDs who graduated from Vanderbilt University between 1997-2021. We categorized careers using an expanded three-tiered taxonomy and flags that delineate key career milestones. We also analyzed career goal changes between matriculation and defense, and the reasons why students became more- or less-interested in research-intensive faculty careers. We linked students career goal at defense to whether they did a postdoc, the duration of time between defense and the first non-training position, the career area of the first non-training position, and the career area of the job at ten years after graduation. Finally, we followed individual careers for ten years after graduation to characterize movement between different career areas over time. We found that most students changed their career goal during graduate school, declining numbers of alumni pursued postdoctoral training, many alumni entered first non-training positions in a different career area than their goal at defense, and the career area of the first non-training position was a good indicator of the job that alumni held 10 years after graduation. Our findings emphasize that students need a wide range of career development opportunities and career mentoring during graduate school to prepare them for futures in research and research-related professions.

scientific communication and education↗

bioRxiv2021

An efficient miRNA knockout approach using CRISPR-Cas9 in Xenopus

In recent years CRISPR-Cas9 knockouts (KO) have become increasingly ultilised to study gene function. MicroRNAs (miRNAs) are short non-coding RNAs, 20-22 nucleotides long, which affect gene expression through post-transcriptional repression. We previously identified miRNAs-196a and -219 as implicated in the development of Xenopus neural crest (NC). The NC is a multipotent stem-cell population, specified during early neurulation. Following EMT NC cells migrate to various points in the developing embryo where they give rise to a number of tissues including parts of the peripheral nervous system and craniofacial skeleton. Dysregulation of NC development results in many diseases grouped under the term neurocristopathies. As miRNAs are so small it is difficult to design CRISPR sgRNAs that reproducibly lead to a KO. We have therefore designed a novel approach using two guide RNAs to effectively drop out a miRNA. We have knocked out miR-196a and miR-219 and compared the results to morpholino knockdowns (KD) of the same miRNAs. Validation of efficient CRISPR miRNA KO and phenotype analysis included use of whole-mount in situ hybridization of key NC and neural plate border markers such as Pax3, Xhe2, Sox10 and Snail2, q-RT-PCR and Sanger sequencing. miRNA-219 and miR-196a KOs both show loss of NC, altered neural plate and hatching gland phenotypes. Tadpoles show gross craniofacial and pigment phenotypes.

developmental biology↗

bioRxiv2018

Variations in neuromodulatory chemical signatures define compartments in macaque cortex

Subcortical neuromodulatory systems exhibit widespread projections that influence the output of cortical circuits. These modulatory systems have been portrayed as providing global signals to the entirety of cortex based on their widespread innervation. This innervation is not necessarily predictive of the levels of the neuromodulatory molecules that actually provide these signals to cortex. In the present study, we examine tissue concentrations of dopamine, noradrenaline, and serotonin to see how they locally vary across multiple areas of the macaque cortex. Our results indicate that different cortical areas exhibit varying levels of dopamine, noradrenaline, and serotonin. Using cluster analysis, we examine how similar cortical regions are to each other, finding that similarities in neurochemical content are shared by areas that exhibit similar functionality. Altogether, these findings demonstrate that neurochemical signatures vary across cortical regions and help define unique, local neuromodulatory signaling compartments.

neuroscience↗