Testing the importance of the 4th CTTC motif for mycorrhizal induced sigras18 expression

Identifier:  TFG:9076

Handle: https://hdl.handle.net/20.500.11797/TFG9076

Authors:  Sans i Rillo, Èlia

Abstract:
Arbuscular mycorrhiza (AM) is an ancient symbiosis between most land plants and AM fungi, which enhances plant nutrition, stress tolerance and resistance to pathogens, while fungi obtain fixed carbon from the host plant. This symbiosis essential in agriculture is tightly regulated through a complex exchange of signals, which leads to the reprogramming of development and metabolism in root arbuscule-containing cells. Some members of the GRAS transcription factor (TF) family are induced upon mycorrhization and play a crucial role in arbuscle accommodation. A great number of them possess a CTTC motif, a cis-regulatory element present in several mycorrhizal-induced TF. In this study, a GUS promoter truncation assay was conducted to contribute to a better understanding of the regulation of the SlGRAS18 TF, which is known to act as a negative regulator of arbuscule formation. The results show that a 240 bp fragment upstream of the SlGRAS18 start codon, containing the 4th CTTC motif, is sufficient to induce its expression, suggesting that this motif may play a key role in the regulation of SlGRAS18 under AM conditions.