Newly identified miRNAs may contribute to aerenchyma formation in sugarcane roots (Plant Direct)

Sugarcane is one of the major crops for sugar and ethanol production and has been successfully used for first generation ethanol production through sucrose fermentation, but second generation ethanol production, through cell wall depolymerization, is still limited. Aerenchyma formation in sugarcane root occurs through the digestion of cell walls but the process controlling it remains unclear. In this paper, Traves et al. show potential epigenetic control during aerenchyma formation through the identification of 39 miRNAs in sugarcane. Gene ontology enrichment analysis of putative transcript targets of these miRNAs revealed that 2.3 and 3.5% of the assigned targets were enriched in cell wall organization and carbohydrate metabolism categories respectively. Considering various modules involved in the formation of aerenchyma, the identified miRNA targets seem to be involved in hormone perception, cell separation, and hemicellulose hydrolysis modules. Identification of 13 miRNAs potentially involved in ethylene perception and signaling supports previous findings on the role of ethylene during aerenchyma formation. Further study of identified miRNAs should provide a deeper understanding of cell wall degradation and hydrolysis of cell wall polymers and contribute to the production of biofuels.  (Summary by Sunita Pathak) Plant Direct  10.1002/pld3.204