Botrydial and botcinins produced by B otrytis cinerea regulate the expression of T richoderma arundinaceum genes involved in trichothecene biosynthesis

• Published in: Molecular plant pathology Vol. 17; no. 7; pp. 1017 - 1031
• Main Authors: Malmierca, Mónica G., Izquierdo‐Bueno, Inmaculada, Mccormick, Susan P., Cardoza, Rosa E., Alexander, Nancy J., Moraga, Javier, Gomes, Eriston V., Proctor, Robert H., Collado, Isidro G., Monte, Enrique, Gutiérrez, Santiago
• Format: Journal Article
• Language: English
• Published: Hoboken John Wiley and Sons Inc 01-09-2016
• Subjects: Original
• ISSN: 1464-6722; 1364-3703
• DOI: 10.1111/mpp.12343

Trichoderma arundinaceum
IBT 40837 (Ta37) and
Botrytis cinerea
produce the sesquiterpenes harzianum A (HA) and botrydial (BOT), respectively, and also the polyketides aspinolides and botcinins (Botcs), respectively. We analysed the role of BOT and Botcs in the Ta37
–B. cinerea
interaction, including the transcriptomic changes in the genes involved in HA (
tri
) and ergosterol biosynthesis, as well as changes in the level of HA and squalene‐ergosterol. We found that, when confronted with
B. cinerea
, the
tri
biosynthetic genes were up‐regulated in all dual cultures analysed, but at higher levels when Ta37 was confronted with the BOT non‐producer mutant
bcbot2Δ
. The production of HA was also higher in the interaction area with this mutant. In Ta37–
bcbot2Δ
confrontation experiments, the expression of the
hmgR
gene, encoding the 3‐hydroxy‐3‐methylglutaryl coenzyme A reductase, which is the first enzyme of the terpene biosynthetic pathway, was also up‐regulated, resulting in an increase in squalene production compared with the confrontation with
B. cinerea
B05.10. Botcs had an up‐regulatory effect on the
tri
biosynthetic genes, with BotcA having a stronger effect than BotcB. The results indicate that the interaction between Ta37 and
B. cinerea
exerts a stimulatory effect on the expression of the
tri
biosynthetic genes, which, in the interaction zone, can be attenuated by BOT produced by
B. cinerea
B05.10. The present work provides evidence for a metabolic dialogue between
T. arundinaceum
and
B. cinerea
that is mediated by sesquiterpenes and polyketides, and that affects the outcome of the interaction of these fungi with each other and their environment.