1 Introduction Hetzer et al., 2005; Goldberg, 2004 Ellenberg et al., 1997; Yang et al., 1997 Vigers and Lohka, 1991 Xenopus Vigers and Lohka, 1991; Macaulay and Forbes, 1996; Drummond et al., 1999 Wiese et al., 1997; Goldberg et al., 1992; Hetzer et al., 2001 Macaulay and Forbes, 1996 Hetzer et al., 2000; Zhang and Clarke, 2000; Zhang et al., 2002 Hetzer et al., 2001 Goldberg et al., 1992 Bodoor et al., 1999 Goldberg et al., 1997; Kiseleva et al., 2001 Winey et al., 1997 Hetzer et al., 2001 Oertle and Schwab, 2003 Prinjha et al., 2000; Yan et al., 2006 van de Velde et al., 1994 Voeltz et al., 2006 Voeltz et al., 2006 2 Results Ellenberg et al., 1997; Yang et al., 1997; Mattaj, 2004 Ellenberg et al., 1997; Hetzer et al., 2001 Voeltz et al., 2006 2.1 Rtn4a is located at inter-membrane junctions between cytoplasmic vesicles near the NE Xenopus, Morozova and Kiseleva, 2006 Fig. 1 Fig. 1 Fig. 1 Fig. 1 Fig. 1 Xenopus Voeltz et al., 2006 Fig. 1 Fig. 1 Fig. 1 Fig. 1 Fig. 1 2.2 Rtn4a is present on membranes attached to growing NEs Fig. 2 Fig. 2 2.3 Rtn4a localises to the junction between the ONM and membranes attached to it Fig. 2b–d Drummond et al., 1999 Fig. 2 2.4 Rtn4a localises to the edges of flattened membranes Fig. 3 Fig. 3b–f Fig. 4 Fig. 4 Fig. 3 Fig. 3d–f Fig. 5 Fig. 5 2.5 Rtn4a is present at the edges of membranes that are flattening onto the chromatin Goldberg et al., 1992; Macaulay and Forbes, 1996 Xenopus in vitro Goldberg and Allen, 1993; Lohka and Masui, 1984 Goldberg et al., 1992; Wiese et al., 1997 Fig. 6 Drummond et al., 1999 Fig. 6 Fig. 6 Fig. 6 Voeltz et al., 2006 2.6 Disrupting Rtn4a prevents NE growth Voeltz et al., 2006 Xenopus Voeltz et al., 2006 Voeltz et al., 2006 Fig. 7 Fig. 7 4.1 Goldberg et al., 1997; Wiese et al., 1997 Fig. 7 Fig. 7d–g Fig. 7 Fig. 7d–g Fig. 7 Fig. 7d–g Fig. 7 Fig. 7 Hanover et al., 1987 Goldberg et al., 1997 Walther et al., 2002 Walther et al., 2001 Goldberg et al., 1995 Drummond et al., 1999 Voeltz et al., 2006 3 Discussion in vitro Voeltz et al., 2006 Voeltz et al., 2006 De Craene et al., 2006 Voeltz et al., 2006 Voeltz et al., 2006 Smeijers et al., 2006; Yang and Huang, 2002 in vitro Ellenberg et al., 1997 Voeltz et al. 2006 Fig. 7 Yang et al., 1997; Drummond et al., 1999 in vivo in vitro 4 Conclusions Voeltz et al., 2006 4.1 Materials and methods 4.1.1 Xenopus 2 Kiseleva et al. 2004 Maupin and Pollard, 1983 4.1.2 Xenopus 4 2 4.1.3 Immuno-TEM 2 3 4.1.4 Immuno-gold labelling and feiSEM imaging Xenopus Voeltz et al., 2006 4.1.5 In vitro Goldberg et al., 1997 Xenopus Voeltz et al., 2006 2 g 2 Goldberg et al., 1997 4.1.6 in vitro g Goldberg et al., 1997 Appendix A Supplementary data doi:10.1016/j.jsb.2007.08.005 Appendix A Supplementary data Supplementary Figure 1  Supplementary Figure 2  Supplementary Figure 3  Supplementary Figure 4  Supplementary Figure 5  Supplementary Figure 6  Supplementary Figure 7  Supplementary Figure 8  Supplementary Figure 9  Supplementary Figure 10