Genome-wide association and targeted transcriptomic analyses reveal loci and candidate genes regulating preharvest sprouting in barley.

KEY MESSAGE: Genome-wide association study of diverse barley genotypes identified loci, single nucleotide polymorphisms and candidate genes that control seed dormancy and therefore enhance resistance to preharvest sprouting. Preharvest sprouting (PHS) causes significant yield and quality loss in barley and it is strongly associated with the level of seed dormancy. This study performed genome-wide association study using a collection of 255 diverse barley genotypes grown over four environments to identify loci controlling dormancy/PHS. Our phenotypic analysis revealed substantial variation in germination index/dormancy levels among the barley genotypes. Marker-trait association and linkage disequilibrium (LD) decay analyses identified 16 single nucleotide polymorphisms (SNPs) and two QTLs associated with dormancy/PHS, respectively, on chromosome 3H and 5H explaining 6.9% to 11.1% of the phenotypic variation. QTL.5H consist of 14 SNPs of which 12 SNPs satisfy the FDR threshold of α = 0.05, and it may represent the SD2 locus. The QTL on 3H consists of one SNP that doesn't satisfy FDR (α = 0.05). Genes harbouring the significant SNPs were analyzed for their expression pattern in the seeds of selected dormant and non-dormant genotypes. Of these genes, HvRCD1, HvPSRP1 and HvF3H exhibited differential expression between the dormant and non-dormant seed samples, suggesting their role in controlling seed dormancy/PHS. Three SNPs located within the differentially expressed genes residing in QTL.5H explained considerable phenotypic variation (≥ 8.6%), suggesting their importance in regulating PHS resistance. Analysis of the SNP marker data in QTL.5H identified a haplotype for PHS resistance. Overall, the study identified loci, SNPs and candidate genes that control dormancy and therefore play important roles in enhancing PHS resistance in barley through marker-assisted breeding.

Cardiac arrest in spontaneous subarachnoid hemorrhage and associated outcomes.

OBJECTIVE: The authors sought to analyze a large, publicly available, nationwide hospital database to further elucidate the impact of cardiopulmonary arrest (CA) in association with subarachnoid hemorrhage (SAH) on short-term outcomes of mortality and discharge disposition. METHODS: This retrospective cohort study was conducted by analyzing de-identified data from the National (Nationwide) Inpatient Sample (NIS). The publicly available NIS database represents a 20% stratified sample of all discharges and is powered to estimate 95% of all inpatient care delivered across hospitals in the US. A total of 170,869 patients were identified as having been hospitalized due to nontraumatic SAH from 2008 to 2014. RESULTS: A total of 5415 patients (3.2%) were hospitalized with an admission diagnosis of CA in association with SAH. Independent risk factors for CA included a higher Charlson Comorbidity Index score, hospitalization in a small or nonteaching hospital, and a Medicaid or self-pay payor status. Compared with patients with SAH and not CA, patients with CA-SAH had a higher mean NIS Subarachnoid Severity Score (SSS) ± SD (1.67 ± 0.03 vs 1.13 ± 0.01, p < 0.0001) and a vastly higher mortality rate (82.1% vs 18.4%, p < 0.0001). In a multivariable model, age, NIS-SSS, and CA all remained significant independent predictors of mortality. Approximately 18% of patients with CA-SAH survived and were discharged to a rehabilitation facility or home with health services, outcomes that were most predicted by chronic disease processes and large teaching hospital status. CONCLUSIONS: In the largest study of its kind, CA at onset was found to complicate roughly 3% of spontaneous SAH cases and was associated with extremely high mortality. Despite this, survival can still be expected in approximately 18% of patients.

Molecular and functional characterization of a jasmonate resistant gene of wheat (Triticum aestivum L.).

Jasmonates play important roles in several plant developmental processes and responses to biotic and abiotic stresses. This study identified a gene encoding jasmonate resistant 1 (JAR1) protein that catalyzes the production of bioactive jasmonoyl-isoleucine (JA-Ile) from hexaploid wheat (Triticum aestivum L), designated as TaJAR1B. The nucleotide sequence of TaJAR1B and amino acid sequence of the corresponding protein exhibited high identity and similarity with other plant JAR1s. Feeding the culture of E. coli cells heterologously expressing TaJAR1B with jasmonic acid (JA) resulted in the production of JA-Ile, indicating the functionality of TaJAR1B in converting JA to JA-Ile. TaJAR1B was highly expressed in the internodes of adult plants and maturing seeds. Salt treatment induced the expression level of TaJAR1B in seedling tissues. Our results indicate that TaJAR1B encodes a functional JAR and is involved in the regulation of plant growth and developmental processes and response to salinity in wheat.