DSpace Community:
https://hdl.handle.net/2440/10827
2024-03-18T16:10:53ZWhen push comes to shove - RNA polymerase and DNA-bound protein roadblocks
https://hdl.handle.net/2440/139620
Title: When push comes to shove - RNA polymerase and DNA-bound protein roadblocks
Author: Hao, N.; Donnelly, A.J.; Dodd, I.B.; Shearwin, K.E.
Abstract: In recent years, transcriptional roadblocking has emerged as a crucial regulatory mechanism in gene expression, whereby other DNA-bound obstacles can block the progression of transcribing RNA polymerase (RNAP), leading to RNAP pausing and ultimately dissociation from the DNA template. In this review, we discuss the mechanisms by which transcriptional roadblocks can impede RNAP progression, as well as how RNAP can overcome these obstacles to continue transcription. We examine different DNA-binding proteins involved in transcriptional roadblocking and their biophysical properties that determine their effectiveness in blocking RNAP progression. The catalytically dead CRISPR-Cas (dCas) protein is used as an example of an engineered programmable roadblock, and the current literature in understanding the polarity of dCas roadblocking is also discussed. Finally, we delve into a stochastic model of transcriptional roadblocking and highlight the importance of transcription factor binding kinetics and its resistance to dislodgement by an elongating RNAP in determining the strength of a roadblock.2023-01-01T00:00:00ZCombining ecology and technology to kick‐start oyster reef restoration
https://hdl.handle.net/2440/139164
Title: Combining ecology and technology to kick‐start oyster reef restoration
Author: Williams, B.R.; McAfee, D.; Connell, S.D.
Abstract: Techniques that enhance the recruitment of foundation species to restoration sites can inform the ecological development of the restored habitat. However, techniques are often considered in isolation, potentially overlooking synergies from combining them. Native oyster reefs have been lost worldwide, resulting in restoration efforts in systems that are often recruitment limited, or where recruiting oysters must spatially compete with opportunistic species. Here, we present a field-based study that combines ecological knowledge on positive species interactions with novel acoustic technology, both of which are demonstrated to boost oyster recruitment in isolation, to test whether their interaction synergistically enhances the early larval recruitment that drives oyster reef development. At three sites across a 20 ha oyster reef restoration in southern Australia, we used self-made speakers to broadcast healthy reef soundscapes that attract oysters and combine this with artificial kelp that facilitates oyster recruitment by suppressing competitive species (turfing algae). The combination of acoustic enrichment and artificial kelp increased oyster recruitment to the topside of substrate (326.98%increase), whereas only acoustic enrichment increased recruitment to the underside of substrate (126.95% increase). Our findings suggest that the combination ofmultiple techniques and their interactive effectsmight boost the early stages of reef development, providing proof-of-concept that these approaches can help oysters to build and bind reefs (i.e. recruit to the topside and underside, respectively). By combining ecology with technology during the first stages of a developing reef restoration, we show the potential value of these novel approaches to kick-start the recovery of lost oyster reefs.
Description: First published: 03 July 20232023-01-01T00:00:00ZOptimal allocation of nature-based solutions to achieve climate mitigation and adaptation goals
https://hdl.handle.net/2440/138821
Title: Optimal allocation of nature-based solutions to achieve climate mitigation and adaptation goals
Author: Villarreal-Rosas, J.; Rhodes, J.R.; Sonter, L.J.; Possingham, H.P.; Vogl, A.L.
Abstract: 1. Nature-based solutions (NbS) can prevent further climate change and increase local communities' capacity to adapt to the current impacts of climate change. However, the benefits obtained from implementing NbS are not distributed equally across people. Thus, it is key to further understand how people are impacted when implementing NbS. 2. We developed a multi-objective prioritization approach to identify changes in (i) the biophysical provision of ecosystem services, (ii) optimal allocation of NbS and (iii) monetary benefits when targeting climate mitigation versus climate adaptation goals. We used the increase in metric tons of carbon storage as representative of climate mitigation and the decrease in on-site and downstream tons of sediment per year as representative of climate adaptation. 3. Planning strategies that target climate mitigation or climate adaptation goals separately represent a loss of between 30% and 60% of the maximum possible carbon sequestration or sediment retention benefits. Conversely, targeting climate mitigation and climate adaptation goals at the same time captured more than 90% of the maximum possible benefits for all objectives. 4. Priority NbS in the mitigation planning strategy included soil and water conservation and forest rehabilitation, while priority NbS in the adaptation planning strategy included grassland rehabilitation and hill terrace improvement. 5. Targeting mitigation and adaptation goals at the same time captures 35M USD (89% of the maximum attainable) in value of carbon restored and retained, and 2M USD (100% of the maximum attainable) of avoided maintenance costs to the KGA hydropower plant. Conversely, failing to incorporate adaptation goals when developing climate plans only captures 1M of avoided maintenance costs to the KGA hydropower plant. 6. Our approach can be replicated in other locations to promote cost-effective investments in NbS able to secure both global and local benefits to people. This can improve the outcomes of international climate change financial schemes like the Green Climate Fund and the UN-REDD+ program.2023-01-01T00:00:00ZEnhanced mitotic arrest and chromosome resolution for cytogenetic analysis in the eastern mosquitofish, Gambusia holbrooki
https://hdl.handle.net/2440/138679
Title: Enhanced mitotic arrest and chromosome resolution for cytogenetic analysis in the eastern mosquitofish, Gambusia holbrooki
Author: Mousavi, S.E.; Grützner, F.; Patil, J.G.
Abstract: Maximising the number of cells arrested at metaphase and their resolution is fundamentally important for molecular cytogenetic investigations, particularly in fish, which typically yield low mitotic index and have highly condensed chromosomes. To overcome these limitations, fish were injected with a mitotic stimulator (the yeast, Saccharomyces cerevisiae) to improve the mitotic index, and the intercalating agent ethidium bromide to produce elongated chromosomes. Specifically, adults were injected with activated yeast and then Colcemid (0.025 µg/µl solution, 10 µl per 1 g of body weight) at 24-96 h post yeast injections, followed by chromosome preparations from multiple tissues. Results showed that gill tissue had the highest number of dividing cells at 72 h post yeast exposure with no significant (p > 0.05) differences between the sexes. Nonetheless, sex-specific differences in the mitotic index were observed in spleen, kidney, and liver, which may be attributed to sex-specific differences in immune responses. For elongation of mitotic chromosomes, individuals (both sexes) were first injected with activated yeast and after 48 h with ethidium bromide (2 or 4 µg/ml) and Colcemid (0.05 µg/µl solution, 10 µl per 1 g of body weight). Following which, animals were sampled at three time points (1, 4 and 8 h) for chromosome preparations. The results show that the optimum elongation of metaphase chromosomes of males and females was achieved by using 2 µg/ml and 4 µg/ml, respectively, for 1 h. Interestingly, the average mitotic chromosome length (μm) of males and females post-ethidium bromide exposure was significantly different (p < 0.05) for both concentrations, except at 1 h exposure for 2 µg/ml EtBr. Such differences can be attributed to overall chromosomal condensation differences between sexes. Regardless, the increased mitotic index and chromosome resolution could benefit cytogenetic studies in other fish species.2023-01-01T00:00:00Z