Correlation of ATP Citrate Lyase and Acetyl CoA Levels with Trichothecene Production in Fusarium graminearum

Abstract

Thecorrelation of ATP citrate lyase (ACL) and acetyl CoA levels with trichothecene production in Fusarium graminearum was investigated using an inhibitor (precocene II) and an enhancer (cobalt chloride) of trichothecene production by changing carbon sources in liquid medium. When precocene II (30 µM) was added to inhibit trichothecene production in a trichothecene high-production medium containing sucrose, ACL expression was reduced and ACL mRNA level as well as acetyl CoA amount in the fungal cells were reduced to the levels observed in a trichothecene trace-production medium containing glucose or fructose. The ACL mRNA level was greatly increased by addition of cobalt chloride in the trichothecene high-production medium, but not in the trichothecene trace-production medium. Levels were reduced to those level in the trichothecene trace-production medium by addition of precocene II (300 µM) together with cobalt chloride. These results suggest that ACL expression is activated in the presence of sucrose and that acetyl CoA produced by the increased ALC level may be used for trichothecene production in the fungus. These findings also suggest that sucrose is important for the action of cobalt chloride in activating trichothecene production and that precocene II may affect a step down-stream of the target of cobalt chloride.

Search for aflatoxin and trichothecene production inhibitors and analysis of their modes of action

“…Therefore, it seemed that the supply of additional acetyl-CoA to the mevalonate pathway may be a key event for initiating trichothecene production. 68) We quantified the amount of acetyl-CoA in fungal cells cultured with or without precocene II and/or sucrose. Precocene II reduced the amount of acetyl-CoA to the level observed in cells cultured without sucrose, in which trichothecene was not produced.…”

“…Precocene II reduced the amount of acetyl-CoA to the level observed in cells cultured without sucrose, in which trichothecene was not produced. 68) By the proteome analysis with twodimensional differential gel electrophoresis, it was found that expression of ATP citrate lyase (ATPCL) in the presence of sucrose was significantly reduced by precocene II. 68) ATPCL is a key enzyme to produce acetyl-CoA in the fungal cytosol.…”

“…68) By the proteome analysis with twodimensional differential gel electrophoresis, it was found that expression of ATP citrate lyase (ATPCL) in the presence of sucrose was significantly reduced by precocene II. 68) ATPCL is a key enzyme to produce acetyl-CoA in the fungal cytosol. Its deletion affects trichothecene production and its expression is not under the control of TRI6.…”

“…These results suggested that ATPCL expression is activated in the presence of sucrose, and that acetyl-CoA produced by the increased ATPCL may be used for trichothecene production in the fungus. 68) Precocene II may affect both pathways which lead to ATPCL and TRI6 expression in the presence of sucrose.…”

Leucine metabolism regulates TRI6 expression and affects deoxynivalenol production and virulence in Fusarium graminearum

“…Acetyl-CoA, which acts as a starter unit for many secondary metabolites, including polyketides, alkaloids, β lactam antibiotics, etc., can originate from mitochondria and peroxisomes through β-oxidation of lipids (Maggio-Hall et al, 2005). In F. graminearum, the cytosolic acetyl-CoA pool, generated by the action of ATP-citrate lyase, plays an important role in the production of DON (Son et al, 2011;Sakamoto et al, 2013). In addition to acetyl-CoA, other forms of acyl-CoAs also serve as starter units for the biosynthesis of various secondary metabolites.…”