Compared boron uptake and translocation in cotton cultivars

The mobility of boron (B), a commonly deficient micronutrient in cotton, has been shown to be low in the plant phloem. Nevertheless, studies have indicated that cotton cultivars can respond differently to B application. A greenhouse experiment was conducted to compare B absorption and mobility in cotton cultivars grown in nutrient solution. Treatments consisted of three cotton cultivars (FMT 701, DP 604BG and FMX 993), and five B rates (0.0, 2.5, 5.0, 10.0, and 20.0 µmol L-1). Plant growth and development were monitored for four weeks from the appearance of the first square. The time of onset and severity of B deficiency symptoms varied among cotton cultivars. Initial B uptake of cv. DP 604BG was lower than of the other cultivars, but a greater amount of available B in the nutrient solution was required to prevent deficiency symptoms in this cultivar. Boron deficiency impairs cotton growth, with no differences among cultivars, regardless of the time of appearance and intensity of B deficiency symptoms.

Photosynthesis rate, chlorophyll content and initial development of physic nut without micronutrient fertilization

Few studies in Brazil have addressed the need for micronutrients of physic nut focusing on physiological responses, especially in terms of photosynthesis. The objective of this study was to evaluate the effects of omission of boron (B), copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn) on Jatropha curcas L.. The experimental design was a randomized block with four replications. The treatments were complete solution (control) and solution without B, Cu, Fe, Mn, and Zn. We evaluated the chlorophyll content (SPAD units), photosynthetic rate, dry matter production and accumulation of micronutrients in plants, resulting from different treatments. The first signs of deficiency were observed for Fe and B, followed by Mn and Zn, while no symptoms were observed for Cu deficiency. The micronutrient omission reduced the dry matter yield, chlorophyll content and photosynthetic rate of the plants differently for each omitted nutrient. It was, however, the omission of Fe that most affected the development of this species in all parameters evaluated. The treatments negatively affected the chlorophyll content, evaluated in SPAD units, and the photosynthetic rate, except for the omission of B. However this result was probably due to the concentration effect, since there was a significant reduction in the dry matter production of B-deficient plants.

Creatine deficiency syndromes and the importance of creatine synthesis in the brain.

Creatine deficiency syndromes, due to deficiencies in AGAT, GAMT (creatine synthesis pathway) or SLC6A8 (creatine transporter), lead to complete absence or very strong decrease of creatine in CNS as measured by magnetic resonance spectroscopy. Brain is the main organ affected in creatine-deficient patients, who show severe neurodevelopmental delay and present neurological symptoms in early infancy. AGAT- and GAMT-deficient patients can be treated by oral creatine supplementation which improves their neurological status, while this treatment is inefficient on SLC6A8-deficient patients. While it has long been thought that most, if not all, of brain creatine was of peripheral origin, the past years have brought evidence that creatine can cross blood-brain barrier, however, only with poor efficiency, and that CNS must ensure parts of its creatine needs by its own endogenous synthesis. Moreover, we showed very recently that in many brain structures, including cortex and basal ganglia, AGAT and GAMT, while found in every brain cell types, are not co-expressed but are rather expressed in a dissociated way. This suggests that to allow creatine synthesis in these structures, guanidinoacetate must be transported from AGAT- to GAMT-expressing cells, most probably through SLC6A8. This new understanding of creatine metabolism and transport in CNS will not only allow a better comprehension of brain consequences of creatine deficiency syndromes, but will also contribute to better decipher creatine roles in CNS, not only in energy as ATP regeneration and buffering, but also in its recently suggested functions as neurotransmitter or osmolyte.

Compared boron uptake and translocation in cotton cultivars

O boro (B) tem baixa mobilidade no floema das plantas e é reconhecidamente o micronutriente cuja deficiência é mais comum no algodoeiro. Neste trabalho foi estudada a absorção e mobilidade do B em cultivares de algodão. O experimento foi conduzido em casa de vegetação, e as plantas foram cultivadas em solução nutritiva. Os tratamentos foram constituídos de três cultivares de algodão (FMT 701, DP 604BG e FMX 993) e cinco doses de B (0,0; 2,5; 5,0; 10,0 e 20,0 µmol L-1). As avaliações foram feitas em quatro semanas consecutivas, a partir da primeira semana após emissão do primeiro botão floral. A época de aparecimento e a intensidade de sintomas de deficiência de boro entre cultivares de algodão são diferentes. A cultivar DP604BG é inicialmente menos exigente em B, porém há necessidade de maior disponibilidade desse micronutriente no meio nutritivo para evitar o aparecimento de deficiência. O crescimento do algodoeiro é prejudicado pela carência de B, independentemente das diferenças no aparecimento de sintomas, não havendo diferença entre as cultivares.

Boron uptake and translocation in some cotton cultivars

Boron (B) is the most deficient micronutrient in cotton (Gossypium hirsutum L.). It is generally accepted that B is immobile in cotton phloem, but some cultivars could remobilize the nutrient. In order to further understand B uptake and mobility in various cotton cultivars two experiments were conducted.In experiment-1, cotton cultivars were grown in B-10 enriched or natural abundance nutrient solutions for 4 weeks and transferred to nutrient solutions ranging from deficient to sufficient in B. In experiment-2 B-10 enriched boric acid was applied to cotton leaves and B mobilization was determined.In deficient plants, B previously supplied to roots was remobilized from older to younger plant tissues, but the amount was insufficient to maintain growth. Boron deficiency symptoms appeared and progressed with time. Boron applied to leaves was taken up and remobilized within 24 h. Boron mobilization was higher to plant parts above the treated region.Boron uptake and mobilization was similar among cotton cultivars. Boron applied to cotton leaves shows a preferential translocation to younger tissues. Foliar sprays of B to cotton may be used to cope with a temporary deficiency, but to achieve full growth and development B must be available to cotton throughout the plant cycle.

The consequences of growth hormone deficiency in adulthood, and the effects of growth hormone replacement

The availability of recombinant human growth hormone (GH) has resulted in investigation of the role of GH in adulthood and the effects of GH replacement in the GH-deficient adult. These studies have led to the recognition of a specific syndrome of GH-deficiency, characterized by symptoms, signs and investigative findings. Adults with long-standing growth hormone deficiency are often overweight, have altered body composition, with reduced lean body mass (LBM), increased fat mass (FM), reduced total body water and reduced bone mass. In addition, there is reduced physical and cardiac performance, altered substrate metabolism and an abnormal lipid profile predisposing to the development of cardiovascular disease. Adults with GH deficiency report reduced psychological well-being and quality of life. These changes may contribute to the morbidity and premature mortality observed in hypopituitary adults on conventional replacement therapy. GH treatment restores LBM, reduces FM, increases total body water and increases bone mass. Following GH therapy, increases are recorded in exercise capacity and protein synthesis, and "favourable" alterations occur in plasma lipids. In addition, psychological well-being and quality of life improve with replacement therapy. GH is well tolerated; adverse effects are largely related to fluid retention and respond to dose adjustment. It is likely that GH replacement will become standard therapy for the hypopituitary adult in the near future. The benefits of GH replacement in the GH-deficient adult have been unequivocally demonstrated in studies lasting up to 3 years. The results of longer term studies are awaited to determine whether these benefits are sustained over a lifetime.

Inhibition and deficiency of the immunoproteasome subunit LMP7 attenuates LCMV-induced meningitis

In addition to antigen processing, immunoproteasomes were recently shown to exert functions influencing cytokine production by monocytes and T cells, T-helper cell differentiation, and T-cell survival. Moreover, selective inhibition of the immunoproteasome subunit LMP7 ameliorated symptoms of autoimmune diseases including CD4(+) T-cell mediated EAE. In this study, we show that LMP7 also plays a crucial role in the pathogenesis of lymphocytic choriomeningitis virus (LCMV)-induced meningitis mediated by CTLs. Mice lacking functional LMP7 display delayed and reduced clinical signs of disease accompanied by a strongly decreased inflammatory infiltration into the brain. Interestingly, we found that selective inhibition and genetic deficiency of LMP7 affect the pathogenesis of LCMV-induced meningitis in a distinct manner. Our findings support the important role of LMP7 in inflammatory disorders and suggest immunoproteasome inhibition as a novel strategy against inflammation-induced neuropathology in the CNS.

Boron nutrition and chilling tolerance of warm climate crop species

Background Field observations and glasshouse studies have suggested links between boron (B)-deficiency and leaf damage induced by low temperature in crop plants, but causal relationships between these two stresses at physiological, biochemical and molecular levels have yet to be explored. Limited evidence at the whole-plant level suggests that chilling temperature in the root zone restricts B uptake capacity and/or B distribution/utilization efficiency in the shoot, but the nature of this interaction depends on chilling tolerance of species concerned, the mode of low temperature treatment (abrupt versus gradual temperature decline) and growth conditions (e.g. photon flux density and relative humidity) that may exacerbate chilling stress. Scope This review explores roles of B nutrition in chilling tolerance of continual root or transient shoot chills in crop species adapted to warm season conditions. It reviews current research on combined effects of chilling temperature (ranging from > 0 to 20 degrees C) and B deficiency on growth and B nutrition responses in crop species differing in chilling tolerance. Conclusion For subtropical/tropical species (e.g. cucumber, cassava, sunflower), root chilling at 10-17 degrees C decreases B uptake efficiency and B utilization in the shoot and increases the shoot : root ratio, but chilling-tolerant temperate species (e.g. oilseed rape, wheat) require much lower root chill temperatures (2-5 degrees C) to achieve the same responses. Boron deficiency exacerbates chilling injuries in leaf tissues, particularly under high photon flux density. Suggested mechanisms for B x chilling interactions in plants are: (a) chilling-induced reduction in plasmalemma hydraulic conductivity, membrane fluidity, water channel activity and root pressure, which contribute to the decrease in root hydraulic conductance, water uptake and associated B uptake; (b) chilling-induced stomatal dysfunction affecting B transport from root to shoot and B partitioning in the shoot; and (c) B deficiency induced sensitivity to photo-oxidative damage in leaf cells. However, specific evidence for each of the mechanisms is still lacking. Impacts of B status on chilling tolerance in crop species have important implications for the management of B supply during sensitive stages of growth, such as early growth after planting and early reproductive development, both of which can coincide with the occurrence of chilling temperatures in the field.

Effect of root zone temperature on oilseed rape (Brassica napus) response to boron

Oilseed rape (Brassica napus) is sensitive to low boron (B) supply, and its growth response to B may be influenced by soil temperature. To test the relationship between B and temperature, oilseed rape (cv. Hyola 42) seedlings were grown at 10 degrees C (low) root zone temperature (RZT) with B supply from deficient to adequate B levels until growth of low B plants just began to slow down. Half of the pots were then transferred to 20 degrees C (warm) RZT for 11 days before they were moved back to 10 degrees C RZT for the final 4 days. Both plant dry mass and B uptake increased after plants were exposed to warm RZT. However, plant B deficiency was exacerbated by warm RZT in low B plants because of increased relative growth rate and shoot-root ratio without a commensurate increase in B uptake rate. It is concluded that RZT above the critical threshold for chilling injury in oilseed rape can nevertheless affect the incidence of B deficiency by altering shoot-root ratio and hence the balance between shoot B demand and B uptake.

Decoding Agc1 deficiency: bioinformatics approaches to unveil the functional implications of Slc25a12 on the transcriptome and epigenome

In the brain, mutations in SLC25A12 gene encoding AGC1 cause an ultra-rare genetic disease reported as a developmental and epileptic encephalopathy associated with global cerebral hypomyelination. Symptoms of the disease include diffused hypomyelination, arrested psychomotor development, severe hypotonia, seizures and are common to other neurological and developmental disorders. Amongst the biological components believed to be most affected by AGC1 deficiency are oligodendrocytes, glial cells responsible for myelination. Recent studies (Poeta et al, 2022) have also shown how altered levels of transcription factors and epigenetic modifications greatly affect proliferation and differentiation in oligodendrocyte precursor cells (OPCs). In this study we explore the transcriptomic landscape of Agc1 in two different system models: OPCs silenced for Agc1 and iPSCs from human patients differentiated to neural progenitors. Analyses range from differential expression analysis, alternative splicing, master regulator analysis. ATAC-seq results on OPCs were integrated with results from RNA-Seq to assess the activity of a TF based on the accessibility data from its putative targets, which allows to integrate RNA-Seq data to infer their role as either activators or repressors. All the findings for this model were also integrated with early data from iPSCs RNA-seq results, looking for possible commonalities between the two different system models, among which we find a downregulation in genes encoding for SREBP, a transcription factor regulating fatty acids biosynthesis, a key process for myelination which could explain the hypomyelinated state of patients. We also find that in both systems cells tend to form more neurites, likely losing their ability to differentiate, considering their progenitor state. We also report several alterations in the chromatin state of cells lacking Agc1, which confirms the hypothesis for which Agc1 is not a disease restricted only to metabolic alterations in the cells, but there is a profound shift of the regulatory state of these cells.

Deficiência em micronutrientes em mudas de sangra d'agua (Croton urucurana, Baill.)

This study had the following objectives: to induce and describe symptoms of deficiency of boron (B), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo) and zinc (Zn), determining the effect on the mineral composition of leaves. The experiment was developed in a green house and used diagnosis technique by subtraction. The experimental design usedn was a randomized blocks, with seven treatments and three replicates. It was verified that micronutrient omission led to morphological alterations which, in turn, caused visual symptoms. The symptoms caused by the omission of Cu, Mn and Zn were the first to appear, and were followed by those of B, Fe and Mo. The omission of B, Mn and Zn was responsible for the more pronounced reduction in height and stem diameter.

BORON UPTAKE AND DISTRIBUTION IN FIELD GROWN CITRUS TREES

In low fertility tropical soils, boron (B) deficiency impairs fruit production. However, little information is available on the efficiency of nutrient application and use by trees. Therefore, this work verified the effects of soil and foliar applications of boron in a commercial citrus orchard. An experiment was conducted with fertigated 4-year-old `Valencia` sweet orange trees on `Swingle` citrumelo rootstock. Boron (isotopically-enriched 10B) was supplied to trees once or twice in the growing season, either dripped in the soil or sprayed on the leaves. Trees were sampled at different periods and separated into different parts for total B contents and 10B/11B isotope ratios analyses. Soil B applied via fertigation was more efficient than foliar application for the organs grown after the B fertilization. Recovery of labeled B by fruits was 21% for fertigation and 7% for foliar application. Residual effects of nutrient application in the grove were observed in the year after labeled fertilizer application, which greater proportions derived from the soil supply.

Phytoplasma closely related to the pigeon pea witches`-broom phytoplasma (16Sr IX) is associated with citrus huanglongbing symptoms in the state of Sao Paulo, Brazil

In February 2007, sweet orange trees with characteristic symptoms of huanglongbing (HLB) were encountered in a region of Sao Paulo state (SPs) hitherto free of HLB. These trees tested negative for the three liberibacter species associated with HLB. A polymerase chain reaction (PCR) product from symptomatic fruit columella DNA amplifications with universal primers fDI/rPI was cloned and sequenced. The corresponding agent was found to have highest 16S rDNA sequence identity (99%) with the Pigeon pea witches`-broom phytoplasma of group 16Sr IX. Sequences of PCR products obtained with phytoplasma 16S rDNA primer pairs fU5/rU3, fU5/P7 confirm these result.,;. With two primers D7f2/D7r2 designed based oil the 16S rDNA Sequence of the cloned DNA fragment, positive amplifications were obtained from more than one hundred samples including symptomatic fruits and blotchy mottle leaves. Samples positive for phytoplasmas were negative for liberibacters, except for four samples, which were positive for both the phytoplasma and `Candidatus Liberibacter asiaticus`. The phytoplasma was detected by electron microscopy in the sieve tubes of midribs from symptomatic leaves. These results Show that a phytoplasma of group IX is associated with citrus HLB symptoms ill northern, central, and Southern SPs. This phytoplasma has very probably been transmitted to citrus from an external Source of inoculum, but the Putative insect vector is not yet known.

Genetic basis of inosine triphosphate pyrophosphohydrolase (ITPA) deficiency

Inosine triphosphate pyrophosphohydrolase (ITPase) deficiency is a common inherited condition characterized by the abnormal accumulation of inosine triphosphate (ITP) in erythrocytes. The genetic basis and pathological consequences of ITPase deficiency are unknown. We have characterized the genomic structure of the ITPA gene, showing that it has eight exons. Five single nucleotide polymorphisms were identified, three silent (138GMA, 561GMA, 708GMA) and two associated with ITPase deficiency (94CMA, IVS2+21AMC). Homozygotes for the 94CMA missense mutation (Pro32 to Thr) had zero erythrocyte ITPase activity, whereas 94CMA heterozygotes averaged 22.5% of the control mean, a level of activity consistent with impaired subunit association of a dimeric enzyme. ITPase activity of IVS2+21AMC homozygotes averaged 60% of the control mean. In order to explore further the relationship between mutations and enzyme activity, we examined the association between genotype and ITPase activity in 100 healthy controls. Ten subjects were heterozygous for 94CMA (allele frequency: 0.06), 24 were heterozygotes for IVS2+21AMC (allele frequency: 0.13) and two were compound heterozygous for these mutations. The activities of IVS2+21AMC heterozygotes and 94CMA/IVS2+21AMC compound heterozygotes were 60% and 10%, respectively, of the normal control mean, suggesting that the intron mutation affects enzyme activity. In all cases when ITPase activity was below the normal range, one or both mutations were found. The ITPA genotype did not correspond to any identifiable red cell phenotype. A possible relationship between ITPase deficiency and increased drug toxicity of purine analogue drugs is proposed.

Iron deficiency, general health and fatigue: Results from the Australian Longitudinal Study on Women's Health

Associations between self-reported 'low iron', general health and well-being, vitality and tiredness in women, were examined using physical (PCS) and mental (MCS) component summary and vitality (VT) scores from the MOS short-form survey (SF-36). 14,762 young (18-23 years) and 14,072 mid-age (45-50 years) women, randomly selected from the national health insurance commission (Medicare) database, completed a baseline mailed self-report questionnaire and 12,328 mid-age women completed a follow-up questionnaire 2 years later. Young and mid-age women who reported (ever) having had 'low iron' reported significantly lower mean PCS, MCS and VT scores, and greater prevalence of 'constant tiredness' at baseline than women with no history of iron deficiency [Differences: young PCS = -2.2, MCS = -4.8, VT = -8.7; constant tiredness: 67% vs. 45%; mid-age PCS = -1.4, MCS = -3.1, VT = -5.9; constant tiredness: 63% vs. 48%]. After adjusting for number of children, chronic conditions, symptoms and socio-demographic variables, mean PCS, MCS and VT scores for mid-age women at follow-up were significantly lower for women who reported recent iron deficiency (in the last 2 years) than for women who reported past iron deficiency or no history of iron deficiency [Means: PCS - recent = 46.6, past = 47.8, never = 47.7; MCS - recent = 45.4, past = 46.9, never = 47.4; VT - recent = 54.8, past = 57.6, never = 58.6]. The adjusted mean change in PCS, MCS and VT scores between baseline and follow-up were also significantly lower among mid-age women who reported iron deficiency only in the last 2 years (i.e. recent iron deficiency) [Mean change: PCS = -3.2; MCS = -2.1; VT = -4.2]. The results suggest that iron deficiency is associated with decreased general health and well-being and increased fatigue.