Glycerol biosynthesis plays an essential role in mediating cold tolerance the red imported fire ant, Solenopsis invicta

Abstract

The red imported fire ant (RIFA), Solenopsis invicta Buren is native to South America and known as a global problematic invasive species. At low temperatures, several investigations have demonstrated an increase in glycerol as a primary rapid cold hardening (RCH) component and an increase in the supercooling point. Two genes, glycerol-3-phosphate dehydrogenase (GPDH) and glycerol kinase (GK), have been identified as being involved in the glycerol production process. In this study, one GPDH and two GK sequences were extracted from RIFA transcriptome analysis (Si-GPDH, Si-GK1, and Si-GK2). All three genes were expressed in different body parts and different tissues of S. invicta that Si-GK2 showed a higher expression level than the others. According to gene expression levels by qRT-PCR analysis, the highest expression levels of three genes were observed in fat body tissues. After 1 h of exposure to low temperatures (5°C or lower), the mRNA levels of these genes significantly increased, according to expression analyses. RNA interference (RNAi) of Si-GPDH or Si-GK1 and Si-GK2 exhibited a significant downregulation at the mRNA level. The mortality rate of treated RIFA by double-stranded RNA (dsRNA) specific to GPDH and GK2 significantly increased at low temperatures. This study indicates that GPDH and GK2 as glycerol biosynthesis genes in RIFA have a high expression

Gene expression differentials driven by mass rearing and artificial selection in black soldier fly colonies

“…Genes involved in carbohydrate metabolism (e.g., LOC119649137, LOC119655675) were expressed at a higher level in the SEL cohort (Figure 10). Notably, LOC119649137, which was annotated as FGGY carbohydrate kinase ( FGGY ), is involved in the biosynthesis of glycerol, with elevated expression of this gene occurring in response to temperature changes in the red imported fire ant, Solenopsis invicta (Vatanparast et al, 2021), and the oriental tobacco budworm, Helicoverpa assulta (Cha & Lee, 2022). In both cases, higher levels of FGGY expression drove increased glycerol synthesis which, in turn, improved insect survival rates under scenarios of cold stress (Cha & Lee, 2022; Vatanparast et al, 2021).…”

“…Notably, LOC119649137, which was annotated as FGGY carbohydrate kinase ( FGGY ), is involved in the biosynthesis of glycerol, with elevated expression of this gene occurring in response to temperature changes in the red imported fire ant, Solenopsis invicta (Vatanparast et al, 2021), and the oriental tobacco budworm, Helicoverpa assulta (Cha & Lee, 2022). In both cases, higher levels of FGGY expression drove increased glycerol synthesis which, in turn, improved insect survival rates under scenarios of cold stress (Cha & Lee, 2022; Vatanparast et al, 2021). The higher expression of this gene in the present study was positively associated with increased larval weight ( r = 0.509, FDR‐corrected p < 0.05; Table S6), and is likely due to increased accumulation of glycogen in the fat body of SEL larvae.…”

Trehalose-6-Phosphate Synthase Contributes to Rapid Cold Hardening in Invasive Insect Lissorhoptrus oryzophilus (Coleoptera: Curculionidae) by Regulating Trehalose Metabolism

“…During spring and autumn, RCH can significantly enhance the survival rates of insects, particularly when temperatures are prone to fluctuations or sharp declines. Previous studies have demonstrated increased survival rates under low temperatures following RCH in different insect species, including Agasicles hygrophila, Helicoverpa assulta, Solenopsis invicta, and Chilo suppressalis [3][4][5][6].…”