Microsatellite association with seed protein content and flowering time in Nigerian cowpea cultivars

Cowpea microsatellites were evaluated for their potential to be used as markers associated with seed protein content and plant flowering time. Seeds with high and low protein content as well as plants with early and late flowering time were selected from 104 Nigerian cowpea accessions. Fifteen (15) microsatellite primer pairs were tested for amplification of microsatellite sequences using PCR and seven pairs amplified a single-locus. Sequence analysis showed a high level of diversity between the analysed genotypes. Although, none of the microsatellites allowed clustering for protein content, one primer pair, VM68, detected a (AG)12-repeat microsatellite allele, which was present only in plants with late flowering. This microsatellite might possibly be useful as a marker associated with late-flowering time.http://www.academicjournals.org/AJBRnf201

Potential use of phytocystatins in crop improvement, with a particular focus on legumes

Phytocystatins are a well-characterized class of naturally-occurring protease inhibitors that function by preventing the catalysis of papain-like cysteine proteases. The action of cystatins in biotic stress resistance has been intensively studied but relatively little is known about their functions in plant growth and defence responses to abiotic stresses, such as drought. Extreme weather events such as drought and flooding will become more frequent as a result of climate change. The concepts that changes in cellular protein content and composition are required for acclimation to different abiotic stresses and that these adjustments are achieved through regulation of proteolysis are widely accepted. However, the nature and regulation of the protein turnover machinery that underpins essential stress-induced cellular re-structuring remains poorly characterised. Cysteine proteases are intrinsic to the genetic programs that underpin developmental senescence, but their functions in stress-induced senescence are poorly defined. While much remains uncertain regarding the individual cysteine protease targets of endogenous cystatins and their precise functions in the regulation of physiological processes are largely unknown, current evidence suggests that manipulation of cysteine protease activities by engineered cystatin expression might be used for to improve the resilience and quality of crop plants in the face of climate change.This work was funded by FP7-PIRSES-GA-2008-230830 (LEGIM) and PIIF-GA-2011- 299347 (Soylife; K.K.). This work was further funded by the International Foundation of Science (IFS grant C/5151-1), the NRF Thuthuka program (B.J.V.) and the NRF Incentive Funding program for rated researchers (K.K.). The funding received from the Genomic Research Institute, University of Pretoria, is hereby also acknowledged. S.G.V.W. thank the NRF/DST in South Africa for bursaries.http://jxb.oxfordjournals.org2016-06-30hb201

Agroinfiltration contributes to VP1 recombinant protein degradation

There is a growing interest in applying tobacco agroinfiltration for recombinant protein production in a plant based system. However, in such a system, the action of proteases might compromise recombinant protein production. Protease sensitivity of model recombinant foot-and-mouth disease (FMD) virus P1-polyprotein (P1) and VP1 (viral capsid protein 1) as well as E. coli glutathione reductase (GOR) were investigated. Recombinant VP1 was more severely degraded when treated with the serine protease trypsin than when treated with the cysteine protease papain. Cathepsin L- and B-like as well as legumain proteolytic activities were elevated in agroinfiltrated tobacco tissues and recombinant VP1 was degraded when incubated with such a protease-containing tobacco extract. In silico analysis revealed potential protease cleavage sites within the P1, VP1 and GOR sequences. The interaction modelling of the single VP1 protein with the proteases papain and trypsin showed greater proximity to proteolytic active sites compared to modelling with the entire P1-polyprotein fusion complex. Several plant transcripts with differential expression were detected 24 hr post-agroinfiltration when the RNA-seq technology was applied to identify changed protease transcripts using the recently available tobacco draft genome. Three candidate genes were identified coding for proteases which included the Responsive-to-Desiccation-21 (RD21) gene and genes for coding vacuolar processing enzymes 1a (NbVPE1a) and 1b (NbVPE1b). The data demonstrates that the tested recombinant proteins are sensitive to protease action and agroinfiltration induces the expression of potential proteases that can compromise recombinant protein production.The National Research Foundation (NRF) and the Genomics Research Institute (GRI), South Africa as well as NRF incentive funding to Karl Kunert and a NRF bursary to Priyen Pillay.http://www.tandfonline.com/loi/kbie202017-08-31hb2016Plant Scienc

Development and use of microsatellites markers for genetic variantion analysis, in the Namibian germplasm, both within and between populations of marama bean (Tylosema esculentum)

Tylosema esculentum (marama) has long been identified as a candidate crop for arid and semi-arid environments due to its success in these environments and the high nutritional value of the seed. Molecular markers are essential for the assessment of the levels of genetic variation present within and between populations of marama as well for future marker-assisted breeding efforts. Microsatellites were isolated using a modified FIASCO enrichment technique. Eighty pairs of primers were designed to amplify across a selected set of perfect microsatellite repeats with greater than 5 repeat units. Of the 80 primer pairs screened, 76% were able to detect polymorphism and 21% gave monomorphic bands while the other 3% gave inconsistent results. Four of the polymorphic SSR’s were used for genetic variation analysis and have proved to be useful and informative markers for assessing intra-specific and interspecific variability of marama bean. Heterozygosity (H) within and between populations of marama bean in the Namibian germplasm ranged from 0.30 to 0.74. Some of the populations had low genetic variation while others had high genetic variation

Review : The future of cystatin engineering

Plant cystatins are naturally occurring protease inhibitors that prevent proteolysis by papain-like cysteine proteases. Their protective action against environmental stresses has been relatively well characterised. Still, there is a need to greatly improve both potency and specificity based on the current rather poor performance of cystatins in biotechnological applications. Research in creating more potent and specific cystatins, including amino acid substitutions in either conserved cystatin motifs and/or at variable amino acid sites, is reviewed. Existing gaps for better understanding of cystatin-protease interactions are further explored. Current knowledge on multi-cystatins or hybrid protease inhibitors involving cystatins as an additional option for cystatin engineering is further outlined along with the nuances of how cystatins with rather unusual amino acid sequences might actually help in cystatin engineering. Finally, future opportunities for application of cystatins are highlighted which include applications in genetically modified transgenic plants for environmental stress protection and also as nutraceuticals, as part of more nutritious food. Further opportunities might also include the possible management of diseases and disorders, often associated with lifestyle changes, and the most immediate and promising application which is inclusion into plant-based recombinant protein production platforms.International Foundation of Science (IFS grant C/5151-1), the NRF Incentive funding for rated researchers (90779) and the NRF National Bioinformatics Functional Genomics program(86947). Funding received from the Genomic Research Institute (GRI), University of Pretoria.http://www.elsevier.com/locate/plantsci2017-05-31hb2016Forestry and Agricultural Biotechnology Institute (FABI)Plant Production and Soil SciencePlant Scienc

Rock snot and lake mud: exploring the history of recent blooms of didymosphenia geminata using information contained in lake sediments

Ecosystem managers have often considered the nuisance diatom species, Didymosphenia gemi¬nata (didymo) as being introduced to the natural environment through human activities; however, observations from early 20th-century surveys challenge this characterization. We use diatoms pre¬served in lake sediment cores to investigate the history of didymo blooms from Gaspésie, Quebec. Relative abundances of diatoms were examined from the dated sediments of Lac Humqui and Lac au Saumon (a lake with an inflowing river currently supporting blooms). Didymo was observed throughout the Lac au Saumon core, demonstrating that it has been present in the region well before the first reports of blooms in 2006. Lac Humqui diatom assemblages experienced a shift in composition with declines in benthic taxa (attached to substrates) and increases in planktonic (free floating) diatoms that began ~1970. Strong relationships between this diatom shift, and increases in regional air temperatures and earlier river ice-out dates were consistent with the expected effects of climate warming on aquatic systems. Our paleolimnological evidence shows that climate warming, rather than human introduction, likely plays an important role in triggering didymo blooms

Seasonal size variation in the predatory cladoceran Bythotrephes cederstroemii in Lake Michigan

1.  Dry weight, body length and spine length were measured for the exotic cladoceran Bythotrephes cederstroemii collected from offshore and inshore stations in southeastern Lake Michigan. Average dry weight of each developmental stage exhibited seasonal variation by a factor of more than 5. 2.  Mean dry weight of Bythotrephes was closely correlated with water temperature. Contrary to the inverse relationship between water temperature and body size frequently observed for other invertebrates, the dry weight of Bythotrephes increased at higher ambient temperatures. 3.  No significant correlation was observed between abundances of major zooplankton taxa and the dry weight of Bythotrephes . An indirect effect of temperature on prey consumption may cause seasonal variation in dry weight of Bythotrephes in Lake Michigan. 4.  Distances between adjacent pairs of barbs, added to the caudal spine with each moult, are significantly shorter in Bythotrephes which produce resting eggs. Less material investment in the exoskeleton of sexually reproducing females was observed in favour of growth and reproduction.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74641/1/j.1365-2427.1994.tb00842.x.pd

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries