The Pin1-CaMKII-AMPA Receptor Axis Regulates Epileptic Susceptibility.

Pin1 is a unique isomerase that regulates protein conformation and function after phosphorylation. Pin1 aberration contributes to some neurological diseases, notably Alzheimer's disease, but its role in epilepsy is not fully understood. We found that Pin1-deficient mice had significantly increased seizure susceptibility in multiple chemical inducing models and developed age-dependent spontaneous epilepsy. Electrophysiologically, Pin1 ablation enhanced excitatory synaptic transmission to prefrontal cortex (PFC) pyramidal neurons without affecting their intrinsic excitability. Biochemically, Pin1 ablation upregulated AMPA receptors and GluA1 phosphorylation by acting on phosphorylated CaMKII. Clinically, Pin1 was decreased significantly, whereas phosphorylated CaMKII and GluA1 were increased in the neocortex of patients with epilepsy. Moreover, Pin1 expression restoration in the PFC of Pin1-deficient mice using viral gene transfer significantly reduced phosphorylated CaMKII and GluA1 and effectively suppressed their seizure susceptibility. Thus, Pin1-CaMKII-AMPA receptors are a novel axis controlling epileptic susceptibility, highlighting attractive new therapeutic strategies.

Combined genome-wide association analysis and transcriptome sequencing to identify candidate genes for flax seed fatty acid metabolism.

Flax seeds have a high oil content and are rich in unsaturated fatty acids, which have advantageous effects in preventing chronic diseases, such as cardiovascular diseases. At present, flax seeds are mainly developed for oil. Therefore, it is of practical significance to identify the candidate genes of fatty acid metabolism in flax seeds for breeding flax seeds with high oil content. In the present study, a natural population of flax containing 224 samples planted in 3 different environments was studied. The genome-wide association analysis (GWAS) of seed fatty acid content was conducted based on specific length amplified fragment sequencing (SLAF-seq) data. Transcriptome sequencing (RNA-seq) of samples from 3 different periods (14 d, 21 d and 28 d after anthesis) during seed development of the low oil variety Shuangya 4 and the high oil variety NEW was performed. The candidate genes for seed fatty acid metabolism were identified by combined analysis of these 2 methods. GWAS detected 16 SNP loci significantly associated with seed fatty acid content, and RNA-seq analysis identified 11,802 differentially expressed genes between high and low oil samples. Pathway enrichment analysis revealed that some differentially expressed genes were classified into fatty acid-related pathways. After comparison of these differentially expressed genes with the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, 20 genes homologous to other species were obtained. After analysis, 10 candidate genes were screened by GWAS and RNA-seq screening. Of these 10 genes, qRT-PCR assays using flax seeds in 5 different developmental stages showed that the expression levels of 6 candidate genes were significantly correlated with 5 fatty acid contents in seeds of the high oil variety NEW. Through metabolic pathway analysis found that 6 genes were involved in important fatty acid metabolic pathways, and some of them also have upstream and downstream regulation relations. The present study combined GWAS and RNA-seq methods to identify candidate genes for fatty acid metabolism in flax seeds, which provided reference for screening of candidate genes with complex traits.

Genomic variations and association study of agronomic traits in flax.

BACKGROUND: Flax (Linum usitatissimum. L) is an ancient oilseed and natural fiber crop. It could be divided into three categories by use, namely oil flax, fiber flax and oil-fiber dual purpose (OF). Cultivated flax is widely used in the food and textile industry. It is of great significance to elucidate the genetic characteristics of flax collections for accelerating the process of breeding improvement in this dual purpose crop. With the development of next-generation sequencing, we can use new methods, such as SLAF-seq (specific-locus amplified fragment sequencing), to decode unknown genomes of species. In this study, a high-through sequencing of flax collections using SLAF-seq was conducted. The evolutionary tendency was defined and candidate genes associated with agronomic traits of flax species were identified by Genome-Wide Association Studying (GWAS). RESULTS: A flax collection consisting of 224 varieties were sequenced by SLAF-seq. In total, 346,639 SLAF tags were developed from all accessions, with an average sequencing depth of 7.19 for each accession. A total of 584,987 SNPs (single nucleotide polymorphism) with an MAF > 0.05 were identified from these SLAFs. The population structure division and phylogenetic analysis indicated a strong divergence among three kinds of flax groups. The genome-wide variation uncovered that oil flax had the highest genetic diversity and was considered to be the ancestor of fiber flax and oil-fiber flax. Sixteen associated peak SNPs for six traits were obtained by GWAS of oil-related traits using EMMAX (efficient mixed-model association eXpedited). Candidate genes and their related pathway were evaluated. A new GWAS was developed for fiber properties using the GLM (General linear model) model and a number of loci were identified. CONCLUSIONS: To our knowledge, this is the first study on discovery multiple loci for important agronomic traits of flax species using GWAS strategy. These results will provide the highest possibility of incorporating both high fiber and good oil traits in a single variety.

Genome-Wide Association Study Identifying Candidate Genes Influencing Important Agronomic Traits of Flax (Linum usitatissimum L.) Using SLAF-seq.

Flax (Linum usitatissimum L.) is an important cash crop, and its agronomic traits directly affect yield and quality. Molecular studies on flax remain inadequate because relatively few flax genes have been associated with agronomic traits or have been identified as having potential applications. To identify markers and candidate genes that can potentially be used for genetic improvement of crucial agronomic traits, we examined 224 specimens of core flax germplasm; specifically, phenotypic data for key traits, including plant height, technical length, number of branches, number of fruits, and 1000-grain weight were investigated under three environmental conditions before specific-locus amplified fragment sequencing (SLAF-seq) was employed to perform a genome-wide association study (GWAS) for these five agronomic traits. Subsequently, the results were used to screen single nucleotide polymorphism (SNP) loci and candidate genes that exhibited a significant correlation with the important agronomic traits. Our analyses identified a total of 42 SNP loci that showed significant correlations with the five important agronomic flax traits. Next, candidate genes were screened in the 10 kb zone of each of the 42 SNP loci. These SNP loci were then analyzed by a more stringent screening via co-identification using both a general linear model (GLM) and a mixed linear model (MLM) as well as co-occurrences in at least two of the three environments, whereby 15 final candidate genes were obtained. Based on these results, we determined that UGT and PL are candidate genes for plant height, GRAS and XTH are candidate genes for the number of branches, Contig1437 and LU0019C12 are candidate genes for the number of fruits, and PHO1 is a candidate gene for the 1000-seed weight. We propose that the identified SNP loci and corresponding candidate genes might serve as a biological basis for improving crucial agronomic flax traits.

Analysis of high risk factors and characteristics of coronary artery in premenopausal women with coronary artery disease.

OBJECTIVE: The aim of this study was to explore the high risk factors and coronary lesion features in premenopausal women with coronary artery disease (CAD) and provide guideline for diagnosis and therapy. METHODS: 114 premenopausal women and 134 postmenopausal women were conducted coronary angiography in our hospital from September, 2012 to September, 2014. According to the results of coronary angiography, premenopausal and postmenopausal women with coronary artery disease were divided into two groups respectively, including 48 premenopausal women with CAD group, 66 premenopausal women with normal coronary artery group, 76 postmenopausal women with CAD group and 58 postmenopausal women with normal coronary artery group. Clinical characteristics and coronary lesion features were analyzed. RESULTS: Incidence rates of hypertension disease and diabetes were higher in premenopausal women with CAD group than control group. Most of premenopausal women suffered from single vessel lesion and the length of impaired vessel was less than 20 mm, meanwhile, postmenopausal women easily confronted from double vessels or mutivessle lesion and the length of impaired vessel was more than 20 mm. Left anterior descending coronary artery lesion was common for premenopausal women. CONCLUSION: Hypertension disease and diabetes were the main high risk factors for premenopausal women and high triglyceride was the optimal predictable factor, furthermore, single vessel lesion and short artery lesion were common in premenopausal women, which often happened in the anterior descending coronary artery.