Proteomic and lipidomics analyses of high fatty acid AhDGAT3 transgenic soybean reveals the key lipase gene associated with the lipid internal mechanism

Vegetable oil is one of the most important components of human nutrition. Soybean (Glycine max) is an important oil crop worldwide and contains rich unsaturated fatty acids. Diacylglycerol acyltransferase (DGAT) is a key rate-limiting enzyme in the Kennedy pathway from diacylglycerol (DAG) to triacylglycerol (TAG). In this study, we conducted further research using T3 AhDGAT3 transgenic soybean. A high-performance gas chromatography flame ionization detector showed that oleic acid (18:1) content and total fatty acid content of transgenic soybean were significantly higher than those of the wild type (WT). However, linoleic acid (18:2) was much lower than that in the WT. For further mechanistic studies, 20 differentially expressed proteins (DEPs) and 119 differentially expressed metabolites (DEMs) were identified between WT (JACK) and AhDGAT3 transgenic soybean mature seeds using proteomic and lipidomics analyses. Combined proteomic and lipidomics analyses showed that the upregulation of the key DEP (lipase GDSL domain-containing protein) in lipid transport and metabolic process induced an increase in the total fatty acid and 18:1 composition, but a decrease in the 18:2 composition of fatty acids. Our study provides new insights into the deep study of molecular mechanism underlying the enhancement of fatty acids in transgenic soybeans, especially oleic acid and total fatty acid, which are enhanced by over-expression of AhDGAT3.

Production and Quantification of Virulence Factors in Malassezia Species

A total of 77 strains of Malassezia were included in this study. Biofilm production and hydrolytic enzymes were studied by using specific solid media. Real-time Reverse Transcriptase qPCR method was applied to determine overexpression of genes encoding extracellular enzyme. All included Malassezia species produced biofilms. No statistical significant difference was observed between biofilm formation of the Malassezia species (P = 0.567) . All Malassezia species produced lipase and 95% of M. globosa showed a strong enzymatic activity (Pz=0.55 ± 0.02). Statistical significant difference was observed between the mean keratinase indices of M. slooffiae and the others Malassezia species ( P = 0.005). The overexpression of one or more genes was observed in 100% of strains isolated from patients with folliculitis, in 87.5% for pityriasis versicolor isolates and in 57.14% for the control group isolates. A statistical significant difference of the lipase gene expression ( P = 0.072) was associated with the strains collected from patients with folliculitis vs group control. This investigation provides more information about the frequency of the production of the major enzymes considered to be virulence factors of Malassezia species. Interestingly, the overexpression of one or more genes was observed in strains isolated from patients with Malassezia disorder.

Genome-Wide Identification of GDSL-Type Esterase/Lipase Gene Family in Dasypyrum villosum L. Reveals That DvGELP53 Is Related to BSMV Infection

GDSL-type esterase/lipase proteins (GELPs) characterized by a conserved GDSL motif at their N-terminus belong to the lipid hydrolysis enzyme superfamily. In plants, GELPs play an important role in plant growth, development and stress response. The studies of the identification and characterization of the GELP gene family in Triticeae have not been reported. In this study, 193 DvGELPs were identified in Dasypyrum villosum and classified into 11 groups (clade A–K) by means of phylogenetic analysis. Most DvGELPs contain only one GDSL domain, only four DvGELPs contain other domains besides the GDSL domain. Gene structure analysis indicated 35.2% DvGELP genes have four introns and five exons. In the promoter regions of the identified DvGELPs, we detected 4502 putative cis-elements, which were associated with plant hormones, plant growth, environmental stress and light responsiveness. Expression profiling revealed 36, 44 and 17 DvGELPs were highly expressed in the spike, the root and the grain, respectively. Further investigation of a root-specific expressing GELP, DvGELP53, indicated it was induced by a variety of biotic and abiotic stresses. The knockdown of DvGELP53 inhibited long-distance movement of BSMV in the tissue of D. villosum. This research provides a genome-wide glimpse of the D. villosum GELP genes and hints at the participation of DvGELP53 in the interaction between virus and plants.

Successful Management of a 29-Day-Old Infant with Severe Hyperlipidemia from a Novel Homozygous Variant of GPIHBP1 Gene

Background: Severe hyperlipidemia is characterized by markedly elevated blood triglyceride levels and severe early-onset cardiovascular diseases, pancreatitis, pancreatic necrosis or persistent multiple organ failure if left untreated. It is a rare autosomal recessive metabolic disorder originated from the variants of lipoprotein lipase gene, and previous studies have demonstrated that most cases with severe hyperlipidemia are closely related to the variants of some key genes for lipolysis, such as LPL, APOC2, APOA5, LMF1 and GPIHBP1. Meanwhile, other unidentified causes also exist and are equally worthy of attention.Methods: The 29-day-old infant was diagnosed with severe hyperlipidemia, registering a plasma triglyceride level as high as 25.46 mmol/L. Whole exome sequencing was conducted to explore the possible pathogenic gene variants for this patient.Results: The infant was put on a low-fat diet combined with pharmacological therapy, which was successful in restraining the level of serum triglyceride and total cholesterol to a low to medium range during the follow-ups. The patient was found to be a rare novel homozygous duplication variant—c.45_48dupGCGG (Pro17Alafs*22) in GPIHBP1 gene—leading to a frameshift which failed to form the canonical termination codon TGA. The mutant messenger RNA should presumably produce a peptide consisting of 16 amino acids at the N-terminus, with 21 novel amino acids on the heels of the wild-type protein.Conclusions: Our study expands on the spectrum of GPIHBP1 variants and contributes to a more comprehensive understanding of the genetic diagnosis, genetic counseling, and multimodality therapy of families with severe hyperlipidemia. Our experience gained in this study is also contributory to a deeper insight into severe hyperlipidemia and highlights the importance of molecular genetic tests.