Gene expression response in roots of Medicago truncatula mutants treated with Myc-LCOs

Legumes interact with soil fungi, leading to the development of arbuscular mycorrhizal (AM) roots. Diffusible AM fungal signals were identified as sulphated and non-sulphated LCOs (sMyc-LCOs and nsMyc-LCOs). Applying Myc-LCOs on roots of symbiotic mutants, we used GeneChips to detail the global programme of gene expression in these mutants in response to the external application of Myc-LCOs. Keywords: Expression profiling by array To harvest tissues for transcriptome profiling, three biological replicates consisting of 10 plantlets per treatment were selected. After 6 h of incubation in the climate chamber, 10 plantlets per batch were removed from the treatment (Myc-LCOs) or control solutions and harvested. During harvest, one mm of the root tip of each plantlet was removed and discarded. The remaining 2 to 2.5 cm of the distal root region were cut off and directly frozen in liquid nitrogen.