Glycine max acyl-acyl carrier protein thioesterase B gene overexpression alters lipid content and fatty acid profile of Arabidopsis seeds.

The fatty acyl-acyl carrier protein thioesterase B (FATB ) gene, involved in the synthesis of saturated fatty acids, plays an important role in the content of fatty acid and composition of seed storage lipids. However, the role of FATB in soybeans (Glycine max ) has been poorly characterised. This paper presents a preliminary bioinformatics and molecular biological investigation of 10 hypothetical FATB members. The results revealed that GmFATB1B , GmFATB2A and GmFATB2B contain many response elements involved in defense and stress responses and meristem tissue expression. Moreover, the coding sequences of GmFATB1A and GmFATB1B were significantly longer than those of the other genes. Their expression varied in different organs of soybean plants during growth, with GmFATB2A and GmFATB2B showing higher relative expression. In addition, subcellular localisation analysis revealed that they were mainly present in chloroplasts. Overexpression of GmFATB1A , GmFATB1B , GmFATB2A and GmFATB2B in transgenic Arabidopsis thaliana plants increased the seed oil content by 10.3%, 12.5%, 7.5% and 8.4%, respectively, compared to that in the wild-type and led to significant increases in palmitic and stearic acid content. Thus, this research has increased our understanding of the FATB family in soybeans and provides a theoretical basis for subsequent improvements in soybean quality.

Genome-wide identification and expression analysis of diacylglycerol acyltransferase genes in soybean (Glycine max).

Background: Soybean (Glycine max) is a major protein and vegetable oil source. In plants, diacylglycerol acyltransferase (DGAT) can exert strong flux control, which is rate-limiting for triacylglycerol biosynthesis in seed oil formation. Methods: Here, we identified soybean DGAT genes via a bioinformatics method, thereby laying a solid foundation for further research on their function. Based on our bioinformatics analyses, including gene structure, protein domain characteristics, and phylogenetic analysis, 26 DGAT putative gene family members unevenly distributed on 12 of the 20 soybean chromosomes were identified and divided into the following four groups: DGAT1, DGAT2, WS/DGAT, and cytoplasmic DGAT. Results: The Ka/Ks ratio of most of these genes indicated a significant positive selection pressure. DGAT genes exhibited characteristic expression patterns in soybean tissues. The differences in the structure and expression of soybean DGAT genes revealed the diversity of their functions and the complexity of soybean fatty acid metabolism. Our findings provide important information for research on the fatty acid metabolism pathway in soybean. Furthermore, our results will help identify candidate genes for potential fatty acid-profile modifications to improve soybean seed oil content. Conclusions: This is the first time that in silico studies have been used to report the genomic and proteomic characteristics of DGAT in soybean and the effect of its specific expression on organs, age, and stages.

Tonoplast inositol transporters: Roles in plant abiotic stress response and crosstalk with other signals.

Inositol transporters (INT) are thought to be the pivotal transporters for vital metabolites, in particular lipids, minerals, and sugars. These transporters play an important role in transitional metabolism and various signaling pathways in plants through regulating the transduction of messages from hormones, neurotransmitters, and immunologic and growth factors. Extensive studies have been conducted on animal INT, with promising outcomes. However, only few recent studies have highlighted the importance and complexity of INT genes in the regulation of plant physiology stages, including growth and tolerance to stress conditions. The present review summarizes the most recent findings concerning the role of INT or inositol genes in plant metabolism and the response mechanisms triggered by external stressors. Moreover, we highlight the emerging role of vacuoles and vacuolar INT in plant molecular transition and their related roles in plant growth and development. INTs are the essential mediators of inositol uptake and its intracellular broadcasting for various metabolic pathways where they play crucial roles. Additionally, we report evidence on Na+/inositol transporters, which until now have only been characterized in animals, as well as H+/inositol symporters and their kinetic functions and physiological role and suggest their roles and operating mode in plants. A more comprehensive understanding of the INT functioning system, in particular the coordinated movement of inositol and the relation between inositol generation and other important plant signaling pathways, would greatly advance the study of plant stress adaptation.