Molluscan biomonitor for quantification and impact assessment of estrogenic and metallic contaminants in Australian marine ecosystems

Research Doctorate - Doctor of Philosophy (PhD)Estrogenic compounds have been identified as a potential cause of reproductive effects in aquatic wildlife worldwide. This thesis was focused on the development of a native Australian species, the Sydney rock oyster Saccostrea glomerata, as a biomonitor of estrogenic compounds in Australian marine ecosystems. Biomarkers of estrogenic exposure in S. glomerata were examined under laboratory and field exposures to estrogenic compound/s. Laboratory exposure of 17α- ethynylestradiol (EE2) to S. glomerata elevated vitellogenin (precursor to the female egg yolk protein) production in both females and males in a dose dependent manner but vitellogenin concentrations declined to basal levels after 49 days exposure. Exposure to EE2 was also capable of inducing accelerated female development, enlarged oocytes and an increase in the proportion of females. Increased proportions of females together with histological observations suggested that a complete sex reversal had occurred from male-intersex-female for a proportion of individuals. A novel real-time qPCR assay for S. glomerata vitellogenin was developed. Sequencing of partial fragments of vitellogenin mRNA and vitellogenin genomic DNA allowed the identification of an intron-exon boundary and the development of real-time qPCR primers. Real-time qPCR revealed that female vitellogenin gene expression responded in a dose response fashion in individuals exposed to a concentration gradient of EE2 for 4 days. To further test biomarker utility, S. glomerata were deployed in the receiving waters of Burwood wastewater treatment plant (WWTP) for 6 weeks, during which effluent was analysed for estrogenic compounds and activity. Sewage effluent from Burwood was found to contain both estrogenic compounds and activity, also S. glomerata deployed at Burwood had higher female vitellogenin (both protein and gene expression) and a higher proportion of mature females compared to individuals at reference locations. As S. glomerata is an established biomonitor of metallic contaminants, it was employed for the analysis of heavy metals in individuals deployed at Burwood and reference locations. Concentrations of heavy metals in S. glomerata were found to be at low concentrations and within boundaries of spatial variation. Overall, findings indicate that S. glomerata would be suitable as a biomonitor of estrogenic exposure and effects in the marine environment

CD200R1 promotes interleukin-17 production by group 3 innate lymphoid cells by enhancing signal transducer and activator of transcription 3 activation

Psoriasis is a common chronic inflammatory skin disease with no cure. It is driven by the interleukin (IL)-23/IL-17A axis and type 17 T helper cells; however, recently, group 3 innate lymphoid cells (ILC3s) have also been implicated. Despite being the focus of much research, factors regulating the activity of ILC3s remain incompletely understood. Immune regulatory pathways are particularly important at barrier sites, such as the skin, gut, and lungs, which are exposed to environmental substances and microbes. CD200R1 is an immune regulatory cell surface receptor that inhibits proinflammatory cytokine production in myeloid cells. CD200R1 is also highly expressed on ILCs, where its function remains largely unexplored. We previously observed reduced CD200R1 signaling in psoriasis-affected skin, suggesting that dysregulation may promote disease. Here, we show that contrary to this, psoriasis models are less severe in CD200R1-deficient mice due to reduced IL-17 production. Here, we uncover a key cell-intrinsic role for CD200R1 in promoting IL-23-driven IL-17A production by ILC3s by promoting signal transducer and activator of transcription 3 activation. Therefore, contrary to its inhibitory role in myeloid cells, CD200R1 is required on ILC3 to promote IL-23-stimulated signal transducer and activator of transcription 3 activation, triggering optimal IL-17 production

Dissection of a non-coding risk locus at 1p36.23 identifies ERRFI1 as a novel gene in the pathogenesis of psoriasis and psoriatic arthritis

Background Psoriasis and its associated inflammatory arthritis Psoriatic Arthritis (PsA) are potentially life-ruining conditions associated with numerous comorbidities. A previously-identified genetic risk association for psoriasis and PsA lies in a non-coding region at chromosome 1p36.23, and as such functional validation is required to determine the genetic mechanism contributing to psoriatic disease risk. Results rs11121131 – a variant in tight linkage with rs11121129, the lead GWAS variant for the 1p36.23 association – lies in a putative enhancer active in keratinocytes but not in immune cells. Promoter-capture Hi-C and H3K27Ac HiChIP showed keratinocyte-specific interactions between 1p36.23 and the TNFRSF9/PARK7/ERRFI1 gene locus ∼200Kb upstream of the risk locus. Deletion of the enhancer in HaCat keratinocytes led to a reduction in transcript levels of the gene ERRFI1, a negative regulator of Epidermal Growth Factor Receptor (EGFR) signalling. CRISPR activation of the enhancer also affected ERRFI1 levels, but paradoxically showed that steady-state activation led to repression of ERRFI1, accompanied by significant deposition of H3K27Me3 histone marks at both the enhancer and the ERRFI1 gene locus. ERRFI1 levels were shown to be increased in inflamed skin from a mouse model of psoriasis, further suggesting its involvement in disease. Conclusions These data indicate rs11121131 lies in an enhancer which modulates ERRFI1 expression in keratinocytes, providing a likely risk mechanism for the 1p36.23 risk association. ERRFI1 represents a novel gene in the pathogenesis of psoriasis and PsA – improving our understanding of these diseases – and the ERRFI1/EGFR signalling axis may therefore be a target for new treatment modalities for psoriatic disease

The ‘Tea Test’ - A mobile phone based spectrophotometer protocol to introduce biochemical methods independent of the laboratory

Providing hands-on practical education without access to laboratories during the Covid-19 pandemic has required creativity and innovation. In this paper, co-authored by academic staff and students, we describe an at-home mobile phone based ‘spectrophotometer’ experiment used in an introductory undergraduate biology course. Using colour picker apps, a smartphone can be used to quantify concentration, which we used to compare the strengths of different brands of tea. The protocol is designed to be low-cost and safe to perform outside of a laboratory. It teaches students important biochemical methods such as preparing dilutions, constructing calibration curves, normalising data and testing a hypothesis. We reflect on the experience of developing and using the protocol from a staff and student perspective, which highlights the advantages of this approach in terms of student independence and inclusivity. We also suggest alternative experiments that could be performed using the protocol. We encourage biology educators to think creatively about the possibilities for using mobile phones or at-home experiments in their teaching. Our experience suggests that at-home experiments like this protocol will have value even after the pandemic is over, particularly in terms of inclusivity

LCS 220 A: Creativity and the Arts Spring 2022

Creativity is vital to achievement in many fields, from science, to business and the arts. This course will explore creativity both as a general process of engagement with the world around us and as an introduction to creative cultural expression in the Arts. It will engage students in thinking about creativity as an intrinsic part of their educational, personal and professional lives, as it engages them in creative practice and reflection upon creative process. As part of the class, students collaborated and created a zine.https://digitalcommons.bryant.edu/zine/1007/thumbnail.jp