Fig. 12

Correlative light and electron microscopy analysis of microtubules in Xenopus cells expressing TgDCX. a Montage of images of microtubule rafts viewed in cross-section by EM, from a Xenopus cell expressing TgDCX-mCherryFP. Often the microtubules on one edge of a raft are incomplete tubes (white arrows), as are some of the single microtubules in these cells. The light micrographs at the bottom show fluorescence and DIC images of the sectioned cell, which is also expressing EGFP-α-tubulin. The plane of sectioning is shown by the white bar. TgDCX-mCherryFP is shown in red, EGFP-α-tubulin in green. b Light and electron microscope images of a Xenopus cell expressing mCherryFP-TgDCX71–243 and EGFP-α-tubulin. mCherryFP-TgDCX71–243 is shown in red, EGFP-α-tubulin in green. The plane of section is indicated by the white bar. The EM images show microtubule cross-sections in these cells, which are similar to those in cells expressing full-length TgDCX, quite different from microtubules in untransfected cells (c.f. Fig. 11). c-f Comparison of microtubule shapes and sizes. c&d: a single microtubule with more than 13 pf, and a cluster of three microtubules from TgDCX71–243 transfected cells. Note that the width of the incomplete microtubules is often larger than the complete tubes, suggesting that the gap results from a tube expanding in diameter and splitting open, rather than from loss of protofilaments. e: a 13 pf microtubule from a cell expressing CvDCX1. f: a 13 pf microtubule from an untransfected cell