NOVEL BIOTECHNOLOGICAL APPROACH TO INCREASE ABIOTIC STRESS TOLERANCE AND SEED DEVELOPMENT IN BRASSICA NAPUS

In plants, E3 ubiquitin ligases play crucial roles in facilitating rapid reactions to environmental stresses by triggering the degradation of proteins. The E3 ligase CRL3BPM regulates the stability of specific transcription factors involved in complex biological processes, including growth, development, and stress response. CRL3BPM can recognize and bind to two specific motifs, called PEST and SBC, on targeted transcription factors. CRL3BPM-substrate interaction leads to the buildup of a chain of ubiquitin molecules that serve as a signal for degradation by the 26S proteasome. From signal perception to substrate degradation, this process may only minutes and because of this, E3 ligases are regarded as regulators of quick responses to environmental changes. However, they also represent interesting targets for affecting substrate stability. By modulating their activities to either delay or promote substrate degradation, they can be a suitable tool to improve critical plant traits such as biomass, seed yield, or abiotic stress tolerance.In this master's thesis, Brassica napus plants were transformed with two expression constructs containing either the PEST or the SBC motif. Both constructs were expressed under the control of a WRINKLED1.2 promoter that confers gene expression in young seedlings and developing seeds. The central hypothesis of this study was that expression of the PEST or the SBC motif at specific developmental stages would result in the transient blocking of CRL3BPM activity, leading to extended half-lives of CRL3BPM substrates. Since substrates of CRL3BPM play roles in abiotic stress responses and seed fatty acid biosynthesis, we tested our hypothesis by exposing germinating seeds to abiotic stress and investigated the transgenic plants for altered seed development. We observed that transgenic B. napus expressing the PEST motif under the control of the WRI1.2 promoter significantly increased tolerance under osmotic and salt stress in germinating seedlings and produced heavier seeds. These data support our hypothesis and validate our approach of using an E3 ligase as a novel tool for generating crop plants with improved traits

Sexual and Reproductive Health Rights of Women Living with HIV in South Africa

South Africa‟s constitutional and legal framework reflects the country‟s commitment to women‟s Sexual and Reproductive Health and Rights (SRHR), in line with international commitments. Numerous policies detail the provision of services around sexual and gender-based violence, fertility, maternal, perinatal and newborn health, sexually transmitted infections (including HIV), and cancers of the reproductive system. However, these policies exist in a social climate of extreme inequality, with high rates of poverty and unemployment. Despite almost equal representation of women in government and other high-profile areas, women in South Africa experience unprecedented rates of sexual and gender-based violence, and women‟s autonomy is all too often compromised by poverty, limited access to education, limited access to health care, and ongoing gender inequality that is bolstered by patriarchal norms.DFI

Isothiourea-catalysed enantioselective pyrrolizine synthesis : synthetic and computational studies

We thank Syngenta and the EPSRC (grant code EP/K503162/1) (DGS), and the EPSRC Centre for Doctoral Training in Critical Resource Catalysis (CRITICAT, grant code EP/L016419/1) (ERG,SFM, RWFK) for funding. The European Research Council under the European Union’s Seventh Framework Programme (FP7/2007-2013) ERC Grant Agreement No. 279850 is also acknowledged (JET). ADS thanks the Royal Society for a Wolfson Research Merit Award.The catalytic enantioselective synthesis of a range of cis-pyrrolizine carboxylate derivatives with outstanding stereocontrol (14 examples,>95:5 dr, >98:2 er) through an isothiourea-catalyzed intramolecular Michael addition-lactonisation and ring opening approach from the corresponding enone acid is reported. An optimised and straightforward three-step synthetic route to the enone acid starting materials from readily available pyrrole-2-carboxaldehydes is delineated, with benzotetramisole (5 mol%) proving the optimal catalyst for the enantioselective process. Ring-opening of the pyrrolizine dihydropyranone products with either MeOH or a range of amines leads to the desired products in excellent yield and enantioselectivity. Computation has been used to probe the factors leading to high stereocontrol, with the formation of the observed cis-steroisomer predicted to be kinetically and thermodynamically favoured.Publisher PDFPeer reviewe

Mechanism of Cu-catalyzed iododeboronation : a description of ligand-enabled transmetalation, disproportionation, and turnover in Cu-mediated oxidative coupling reactions

Funding: Biotechnology and Biological Sciences Research Council - BB/R013780/; Engineering and Physical Sciences Research Council - EP/R025754/1, EP/W007517/1, EP/S027165/1; Leverhulme Trust - RF-2022-014.We report a combined experimental and computational study of the mechanism of the Cu-catalyzed arylboronic acid iododeboronation reaction. A combination of structural and density functional theory (DFT) analyses has allowed determination of the identity of the reaction precatalyst with insight into each step of the catalytic cycle. Key findings include a rationale for ligand (phen) stoichiometry related to key turnover events─the ligand facilitates transmetalation via H-bonding to an organoboron boronate generated in situ and phen loss/gain is integral to the key oxidative events. These data provide a framework for understanding ligand effects on these key mechanistic processes, which underpin several classes of Cu-mediated oxidative coupling reactions.Publisher PDFPeer reviewe

New genetic loci link adipose and insulin biology to body fat distribution.

Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms

Microwave Radiometry at Frequencies From 500 to 1400 MHz: An Emerging Technology for Earth Observations

icrowave radiometry has provided valuable spaceborne observations of Earth’s geophysical properties for decades. The recent SMOS, Aquarius, and SMAP satellites have demonstrated the value of measurements at 1400 MHz for observ- ing surface soil moisture, sea surface salinity, sea ice thickness, soil freeze/thaw state, and other geophysical variables. However, the information obtained is limited by penetration through the subsur- face at 1400 MHz and by a reduced sensitivity to surface salinity in cold or wind-roughened waters. Recent airborne experiments have shown the potential of brightness temperature measurements from 500–1400 MHz to address these limitations by enabling sensing of soil moisture and sea ice thickness to greater depths, sensing of temperature deep within ice sheets, improved sensing of sea salinity in cold waters, and enhanced sensitivity to soil moisture under veg- etation canopies. However, the absence of significant spectrum re- served for passive microwave measurements in the 500–1400 MHz band requires both an opportunistic sensing strategy and systems for reducing the impact of radio-frequency interference. Here, we summarize the potential advantages and applications of 500–1400 MHz microwave radiometry for Earth observation and review recent experiments and demonstrations of these concepts. We also describe the remaining questions and challenges to be addressed in advancing to future spaceborne operation of this technology along with recommendations for future research activities

The challenge of preventing extinctions: lessons from managing threatened land snails on Norfolk Island.

Norfolk Island, situated between Australia, New Zealand and New Caledonia, has a rich, narrowly endemic land snail fauna, which has suffered considerably from habitat loss and introduced predators. Eleven species (Stylommatophora, Microcystidae) are currently listed by the IUCN and/or Australia's EPBC Act 1999 as Endangered, Critically Endangered or Extinct. Based on targeted surveys undertaken since 2020, we re-assess the threat status of these taxa. For three species assessed to be at imminent risk of extinction, we report on the implementation of in-situ and ex-situ conservation actions and assess their effectiveness after a three-year period. We document current distributions and abundances of these species and describe experimental conservation methods, such as increased predator control, the erection of predator-proof exclosures, and the establishment of an ex-situ breeding population. We found that the relative abundance of one subspecies, Advena campbellii campbellii, was strongly correlated with monthly rainfalls. Trials of predator-proof exclosures that retain adults but allow juveniles to disperse indicated that snails can be successfully secured from predation. Increased efforts in predator control led to the killing of more rodents and chickens; however, the impact on the snail population is unclear. The ex-situ breeding population had high birth rates initially followed by high adult mortality. Adjustments in husbandry conditions reduced stress levels leading to sustainable birth rates and increased survivorship with the result of rapid population growth. We determined that the ovoviviparous A. campbellii campbellii matures at the age of 3-4 months and has a lifespan of 10-12 months in captivity. We conclude that focused predation studies are needed to determine the impact of introduced predators. The use of exclosures requires further refinement especially regarding feeding schedules. In-situ breeding requires significant time for establishment but can be implemented successfully. We assess three endemic species as Extinct, four as Critically Endangered and two as Vulnerable