MAP2K4 and glaucoma: The present work investigated whether JUN and DDIT3, or their upstream activators MKK4 and MKK7, control degeneration of RGC axons and somas after glaucoma-relevant injuries; including ocular hypertension in aged DBA/2J mice and after mechanical axonal injury (controlled optic nerve crush, CONC) in C57BL/6J mice.