The wild type Col-0 plants and the Sku-6 mutant plants of the Col-0 background were germinated on ISS or on the ground and the gene expression profiles in roots at 4 days or 8 days were established. The Sku6 gene (At2g03680) codes for a protein that localizes to microtubule within the cortical array and putatively acting as an intramolecular linker. The development of Col-0 and Sku-6 plants on orbit differs from that on the ground as demonstrated by the comparison of the gene expression profiles between 4 days old to 8 days old plant in the two environments. However the development of Sku-6 mutant plants also differs from Col-0 at either age and in either environment, suggesting the role of the genetic background in these developmental decisions. The 4 days old Sku-6 roots in orbit engaged more genes than the 4 days old Col-0 roots in orbit but also more than the 4 days old Sku-6 roots on the ground. Overall the 4 days old roots differentially expressed more genes in spaceflight relative to ground than the 8 days old roots of either genotype.