Overexpression of DoUGP Enhanced Biomass and Stress Tolerance by Promoting Polysaccharide Accumulation in Dendrobium officinale

Abstract

Uridine diphosphate glucose pyrophosphorylase (UDP-glucose pyrophosphorylase, UGPase), as one of the key enzymes in polysaccharide synthesis, plays important roles in the growth and development of plants. In this study, the DoUGP gene of Dendrobium officinale was overexpressed. The expression of DoUGP and genes playing roles in the same and other saccharide synthesis pathways was determined, and the total soluble polysaccharide was also tested in wild-type and transgenic seedlings. We also performed freezing and osmotic stress treatments to determine whether overexpression of DoUGP could influence stress resistance in transgenic seedlings. Results showed that mRNA expression levels of DoUGP and its metabolic upstream and downstream genes in the transgenic seedlings were increased compared to the expression of these genes in wild-type seedlings. Additionally, most CSLA genes involved in the biosynthesis of mannan polysaccharides were significantly upregulated. The total polysaccharide and mannose content of transgenic seedlings were increased compared to the content of wild type, and enhanced stress tolerance was found in the overexpressed seedlings compared to the wild type.

Transcriptome Analysis Revealed the Advantages of Room Temperature Preservation of Concentrated Oocystis borgei Cultures for Use in Aquaculture

“…The genes included phosphoglucomutase (PGM) and UTP-glucose-1-phosphate uridylyltransferase (UPG2), which, respectively, facilitate the conversion of Glc-6-P to Glc-1-P and Glc-1-P to UDP glucose. This finding aligns with the observed rise in polysaccharide levels during HT storage, which supports Chen and colleagues' research [48].…”

“…When plants are exposed to temperatures beyond their optimal range, the structure and function of the cell membrane will undergo changes in various properties, such as fluidity, permeability, intercellular signal transduction, and antioxidant capacity [46]. Lipids and carbohydrates play important roles in plant adaptation to temperature changes, and microalgae can regulate the content and types of unsaturated fatty acids to alter the fluidity of cell membranes, while carbohydrates can enhance the tolerance of plant tissues to temperature stress [47,48]. Trehalose can protect the biofilm and protein structure of algae, ensure the activity of enzymes in adverse environments, and higher levels of trehalose can increase the temperature tolerance of algae [49][50][51].…”

Response mechanism of overexpress LBA0625 in Lactococcus lactis NZ9000 at freeze-drying process revealed by transcriptomic analysis

“…The existing dates showed that genetic engineering is a potential method to improve the survival rate of bacteria during freeze-drying. As UGPase plays a highly critical role in cellular integrity, it has been overexpressed in yeast [9] , Dendrobium officinal [10] , Aureobasidium pullulans [2] , and successfully enhanced their freeze-drying tolerance. However, there is little known about the correlation between UGPase with freeze-drying tolerance of LAB.…”