KLF15 and proximal spinal muscular atrophy: However, this effect on Klf15 induction ceased at P7, specifically in SMA mice [18], suggesting that prednisolone-dependent benefits in symptomatic SMA mice may be due to KLF15-independent effects and/or that prednisolone-dependent Klf15 increase in P7 animals may be limited by compensatory inhibitory mechanisms due to already significantly increased Klf15 levels in symptomatic SMA mice compared with controls [18].