Transcriptome analysis of a N. punctiforme sigG mutant. Nostoc punctiforme

Nostoc punctiforme is a filamentous cyanobacterium capable if differentiating normal vegetative cells into nitrogen fixing heterocysts and spore-like akinetes. Here the effects of a sigma factor (sigG) mutation on the transcriptome was analyzed under 1) normal vegetative growth, and 2) following akinete induction. A zwf strain grown with fructose differentiates into akinetes following transfer to darkness. A DNA microarray was used to compare gene expression from the zwf strain to a zwf sigG double mutant two days following akinte induction by darkness. Overall design: Gene expression in a zwf mutant strain was compared to a zwf sigG double mutant strain under normal vegetative growth and at two days following akinete induction. Each experiment used three array slides with two biological replicates. A dye swap was used for one biological replicate.