Trancriptional landscape of Aspergillus niger at breaking of conidial dormancy revealed by RNA-sequencing. Aspergillus niger

Genome-wide analysis was performed to assess the transcriptional landscape of germinating A. niger conidia for first hour using next generation RNA-sequencing. The transcriptome of dormant conidia was shown to be highly differentiated from that of germinating conidia. The breaking of dormancy was associated with increased transcript levels of genes involved in the biosynthesis of proteins, RNA turnover and respiratory metabolism. Increased transcript levels of genes involved in metabolism of nitrate and proline at the onset of germination implies their use as sources of nitrogen. The transcriptome of dormant conidia contained a significant component of antisense transcripts that changed during germination. Dormant conidia contained transcripts of genes involved in fermentation, gluconeogenesis and the glyoxylate cycle. The presence of such transcripts in dormant conidia may indicate the generation of energy from non-carbohydrate substrates during starvation-induced conidiation or for maintenance purposes during dormancy. The immediate onset of metabolism of internal storage compounds after the onset of germination, and the presence of transcripts of relevant genes, suggest that conidia are primed for the onset of germination. For some genes, antisense transcription is regulated in the transition from resting conidia to fully active germinants. Overall design: Duplicate samples from each time point: dormant conidia T0 (DA 21 + DA 22) and conidia germinated for one hour T1 (DA 23 + DA 24)