LCBs are integral components of the nuclear membrane in human cells. (a–c) Live-cell microscopy of HeLa cells expressing mCherry-Farnesyl-5 (red, plasma membrane) incubated for 20 min with 1 µM Sph-NBD (a), S1P-NBD (b), or C6-ceramide-NBD (c). Scale bar, 5 µm. Scale bar in zoomed images, 1 µm.