Supplementary Figure 6: Membrane-targeting lipid modification of full-length (FL) SOS1 allows spontaneous activation of ERK and prolonged response after BCR stimulation.
From: One-way membrane trafficking of SOS in receptor-triggered Ras activation
(a) Farnesylation tag engineered to FL WT hSOS1 (SOS1-F) and point-mutated inactive control (SOS1-F*).
(b) Western blotting shows mobility shift by lipid modification.
(c) Ligand-independent activation of pERK. To note, membrane-anchored full-length SOS1 signals to ERK independent of BCR stimulation as observed on SOSCat-expressing cells (see also, Fig 4e,h)
(d) Time trace of p-ERK response upon BCR stimulation at intermediary SOS1-expressing cells.
BCR-induced ERK activity is prolonged compared to unmodified SOS1 or inactive SOS1-F*.
Shown data are representative of two independent cell cultures and pFLOW experiments. Source data are available online.
