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Seeds of grain legumes are important energy and food sources for humans and animals. However, the yield and quality of legume seeds are limited by the amount of sulfur (S) partitioned to the seeds. The amino acid S-methylmethionine (SMM), a methionine derivative, has been proposed to be an important long-distance transport form of reduced S, and we analyzed whether SMM phloem loading and source-sink translocation are important for the metabolism and growth of pea (Pisum sativum) plants. Transgenic plants were produced in which the expression of a yeast SMM transporter, S-Methylmethionine Permease1 (MMP1, YLL061W), was targeted to the phloem and seeds. Phloem exudate analysis showed that concentrations of SMM are elevated in MMP1 plants, suggesting increased phloem loading. Furthermore, expression studies of genes involved in S transport and metabolism in source organs, as well as xylem sap analyses, support that S uptake and assimilation are positively affected in MMP1 roots. Concomitantly, nitrogen (N) assimilation in root and leaf and xylem amino acid profiles were changed, resulting in increased phloem loading of amino acids. When investigating the effects of increased S and N phloem transport on seed metabolism, we found that protein levels were improved in MMP1 seeds. In addition, changes in SMM phloem loading affected plant growth and seed number, leading to an overall increase in seed S, N, and protein content in MMP1 plants. Together, these results suggest that phloem loading and source-sink partitioning of SMM are important for plant S and N metabolism and transport as well as seed set.

The prevalence of malnutrition in subacute inpatient settings has been reported to be 30-50%. While there are a number of nutrition evaluation tools which have been validated to diagnose malnutrition, the use of a validated nutrition evaluation tool to measure changes in nutritional status during an average length of stay for a subacute inpatient has not yet been tested. This study aims to determine the potential of the full MNA (full Mini Nutritional Assessment) and MNA (Mini Nutritional Assessment Short Form) scores to measure change in nutritional status over an average subacute inpatient stay (21 days).A prospective observational study.The study was performed in three Rehabilitation and Geriatric Evaluation and Management (GEM) wards of the Kingston Centre, Monash Health, Melbourne, Australia.All patients ≥65 years admitted to these wards with an expected length of stay of at least 14 days were considered for inclusion in this study.Nutritional status was assessed on admission using the full MNA as part of usual dietetic care and patients were provided with nutrition intervention/diet therapy based on full MNA classification. Full MNA score (0-30), MNA score (0-14), anthropometry (weight and height) and nutritional biochemistry (serum albumin, transthyretin and C-reactive protein) were compared between admission and day 20.5 ± 2.4.Mean age (± SD) of 83 ± 7 years, n=114. For those patients diagnosed at risk of malnutrition or malnourished (n=103), there were significant increases in full MNA score (1.8 ± 2.4, p0.001), MNA score (0.9 ± 1.7, p0.001), weight (0.6 ± 2.5 kg, p=0.017) and serum albumin (1.4 ± 4.4 g/L, p=0.003) over the study period. All four of the full MNA domain sub-scores, also increased significantly in those patients diagnosed at risk of malnutrition or malnourished (n=103): anthropometric assessment (p0.001), dietary assessment (p0.001), general status assessment (p=0.019) and self-perceived health and nutrition states (p=0.033).Both the MNA and full MNA can be used to evaluate nutrition progress within the subacute inpatient setting over a three week time period, thereby providing clinicians with feedback on a patient's nutrition progress and assisting with ongoing care planning. Due to its ease of use and shorter time required to complete, the MNA may be the preferred nutrition evaluation tool in this setting.

Key MessageAgrobacterium tumefacienswas used to transform radiata pine shoots and to efficiently produce stable genetically modified pine plants. Abstract Micropropagated shoot explants fromPinus radiataD. Don were used to produce stable transgenic plants byAgrobacterium tumefaciensmediated transformation. Using this method any genotype that can be micropropagated could produce stable transgenic lines. As over 80% ofP. radiatagenotypes tested can be micropropagated, this effectively means that any line chosen for superior characteristics could be transformed. There are well established protocols for progressing such germplasm to field deployment. Here we used open and control pollinated seed lines and embryogenic clones. The method developed was faster than other methods previously developed using mature cotyledons. PCR positive shoots could be obtain within 6 months ofAgrobacteriumcocultivation compared with 12 months for cotyledon methods. Transformed shoots were obtained using either kanamycin or geneticin as the selectable marker gene. Shoots were recovered from selection, were tested and were not chimeric, indicating that the selection pressure was optimal for this explant type. GFP was used as a vital marker, and the bar gene, (for resistance to the herbicide Buster®/Basta®) was used to produce lines that could potentially be used in commercial application. As expected, a range of expression phenotypes were identified for both these reporter genes and the analyses for expression were relatively easy.

The intragenic vector system involves identifying functional equivalents of vector components from the genome of a specific crop species (or related species to which it can be hybridised) and using these DNA sequences to assemble vectors for transformation of that plant species. This system offers an attractive alternative to current genetic engineering strategies where vectors are based on DNA sequences that usually originate from bacteria. The construction of intragenic vectors enables the well-defined genetic improvement of plants with all transferred DNA originating from within the gene pool already available to plant breeders. In this manner genes can be introgressed into elite cultivars in a single step without linkage drag and without the incorporation of foreign DNA. The resulting plants are non-transgenic, although they are derived using the tools of molecular biology and plant transformation. The use of intragenic vectors for the transfer of genes from within the gene pools of crops may help to alleviate some of the major public concerns over the deployment of GM crops in agriculture, notably the ethical issue associated with the transfer of DNA across wide taxonomic boundaries. This paper reviews the progress toward the development and use of intragenic vectors and the implications of their use for the genetic improvement of crops.