Vol. 179, No. 4, November 19, 2007. 10.1083/jcb.200706151.

The authors discovered after publication that a reagent had been reported incorrectly. In Table I: Strains and plasmids, the plasmid pMR5029 is listed as SS-3X-GFP-HDEL in pRS414, providing a fluorescent ER-GFP marker. Subsequent work indicated that the plasmid construct is different from indicated. Plasmid pMR5029 actually contains Sec63p-GFP in pRS414, a different ER-GFP marker. This does not alter the major conclusion of the paper that the outer nuclear envelope fuses before the inner nuclear envelope. The authors regret any confusion this may have caused.