Barley sodium content is regulated by natural variants of the Na+ transporter HvHKT1;5

During plant growth, sodium (Na+) in the soil is transported via the xylem from the root to the shoot. While excess Na+ is toxic to most plants, non-toxic concentrations have been shown to improve crop yields under certain conditions, such as when soil K+ is low. We quantified grain Na+ across a barley genome-wide association study panel grown under non-saline conditions and identified variants of a Class 1 HIGH-AFFINITY-POTASSIUM-TRANSPORTER (HvHKT1;5)-encoding gene responsible for Na+ content variation under these conditions. A leucine to proline substitution at position 189 (L189P) in HvHKT1;5 disturbs its characteristic plasma membrane localisation and disrupts Na+ transport. Under low and moderate soil Na+, genotypes containing HvHKT1:5P189 accumulate high concentrations of Na+ but exhibit no evidence of toxicity. As the frequency of HvHKT1:5P189 increases significantly in cultivated European germplasm, we cautiously speculate that this non-functional variant may enhance yield potential in non-saline environments, possibly by offsetting limitations of low available K+

Rhizosphere microbiome and plant growth promotion bacteria isolates enhance salinity tolerance in salt-sensitive Brassica fruticulosa

Soil salinity is a major stress limiting agricultural productivity worldwide. To counteract the adverse effects of salinity, plants from coastal habitats may engage in positive interaction with microbial partners. We recently discovered inland and coastal populations of Brassica fruticulosa with contrasting salinity tolerance. Here we characterize the microbiomes of salt-tolerant (PST) and salt-sensitive (PSS) populations, analyzing the diversity and abundance of bacteria and fungi taxa in bulk soil, rhizosphere, roots, and leaves of eight populations. We tested in a reciprocal transplant experiment the effects of two salt-tolerant (MST) and two salt-sensitive (MSS) rhizospheric microbiomes on PST and PSS plants under high salinity. Inoculation with MST enhanced salinity tolerance, improved growth, nutritional status, and reduced oxidative stress of PSS plants. Later, we isolated 113 bacterial strains from MST, 26 of which grew in 150mM NaCl and exhibited phosphate solubilization and siderophore production mechanisms. Further screening for nitrogen fixation, auxin production, and ACC deaminase activity allowed us to select 15 top candidates for mediating tolerance. Only five strains significantly promoted salt-sensitive plants growth under saline conditions. These findings highlight that the microbiome of species adapted to harsh conditions harbor a reservoir of potentially beneficial microorganisms that may improve plant resilience to salinity

Natural history of liver disease in a large international cohort of children with Alagille syndrome: Results from the GALA study

BACKGROUND AND AIMS: Alagille syndrome (ALGS) is a multisystem disorder, characterized by cholestasis. Existing outcome data are largely derived from tertiary centers, and real-world data are lacking. This study aimed to elucidate the natural history of liver disease in a contemporary, international cohort of children with ALGS. APPROACH AND RESULTS: This was a multicenter retrospective study of children with a clinically and/or genetically confirmed ALGS diagnosis, born between January 1997 and August 2019. Native liver survival (NLS) and event-free survival rates were assessed. Cox models were constructed to identify early biochemical predictors of clinically evident portal hypertension (CEPH) and NLS. In total, 1433 children (57% male) from 67 centers in 29 countries were included. The 10 and 18-year NLS rates were 54.4% and 40.3%. By 10 and 18 years, 51.5% and 66.0% of children with ALGS experienced ≥1 adverse liver-related event (CEPH, transplant, or death). Children (>6 and ≤12 months) with median total bilirubin (TB) levels between ≥5.0 and 10.0 mg/dl were associated with a 4.8 (95% CI, 2.4-9.7) and 15.6 (95% CI, 8.7-28.2) increased risk of transplantation relative to <5.0 mg/dl. Median TB <5.0 mg/dl were associated with higher NLS rates relative to ≥5.0 mg/dl, with 79% reaching adulthood with native liver ( p < 0.001). CONCLUSIONS: In this large international cohort of ALGS, only 40.3% of children reach adulthood with their native liver. A TB <5.0 mg/dl between 6 and 12 months of age is associated with better hepatic outcomes. These thresholds provide clinicians with an objective tool to assist with clinical decision-making and in the evaluation of therapies

Natural History of Liver Disease in a Large International Cohort of Children with Alagille syndrome: Results from The <scp>GALA</scp> Study

Background: Alagille syndrome (ALGS) is a multisystem disorder, characterized by cholestasis. Existing outcome data are largely derived from tertiary centers and real-world data are lacking. This study aimed to elucidate the natural history of liver disease in a contemporary, international, cohort of children with ALGS. Methods: Multicenter retrospective study of children with a clinically and/or genetically confirmed ALGS diagnosis, born Jan-1997 - Aug-2019. Native liver survival (NLS) and event-free survival rates were assessed. Cox models were constructed to identify early biochemical predictors of clinically evident portal hypertension (CEPH) and NLS. Results: 1433 children (57% male) from 67 centers in 29 countries were included. 10 and 18-years NLS rates were 54.4% and 40.3%. By 10 and 18-years, 51.5% and 66.0% of ALGS children experienced ≥1 adverse liver-related event (CEPH, transplant or death). Children (>6 and ≤12 months) with median total bilirubin (TB) levels between ≥5.0 and 10.0 mg/dL were associated with a 4.8 (95% CI 2.4 - 9.7) and 15.6 (95% CI 8.7 - 28.2) increased risk of transplantation relative to <5.0 mg/dL. Median TB <5.0 mg/dL were associated with higher NLS rates relative to ≥5.0 mg/dL, with 79% reaching adulthood with native liver (p<0.001). Conclusions: In this large international cohort of ALGS, only 40.3% of children reach adulthood with their native liver. A TB <5.0 mg/dL between 6-and-12-months of age is associated with better hepatic outcomes. These thresholds provide clinicians with an objective tool to assist with clinical decision-making and in the evaluation of novel therapies

Event-free survival of maralixibat-treated patients with Alagille syndrome compared to a real-world cohort from GALA

Background and Aims: Alagille syndrome (ALGS) is characterized by chronic cholestasis with associated pruritus and extrahepatic anomalies. Maralixibat, an ileal bile acid transporter inhibitor, is an approved pharmacologic therapy for cholestatic pruritus in ALGS. Since long-term placebo-controlled studies are not feasible or ethical in children with rare diseases, a novel approach was taken comparing 6-year outcomes from maralixibat trials with an aligned and harmonized natural history cohort from the Global ALagille Alliance (GALA) stud