Kinase suppressor of Ras 1 is an enzyme that in humans is encoded by the KSR1 gene. Enables 14-3-3 protein binding activity; ATP binding activity; and protein C-terminus binding activity. Involved in positive regulation of MAPK cascade. Located in endoplasmic reticulum and membrane. Part of protein-containing complex. Implicated in breast adenocarcinoma. Biomarker of breast cancer.