Figure 2.

Polar residues in the TR TM are necessary and sufficient to mediate targeting of the TR to a post-Golgi–processing compartment. Equivalent cell numbers of CEFs expressing wild-type TR, Ii_TM 11–19, TR_TM Thr¹¹Gln¹⁷Thr¹⁹, and Ii_TM 11–19 Ala¹¹Ala¹⁷Ala¹⁹ chimeras were pulse labeled for 30 min with trans-³⁵S label and chased with complete medium for various periods of time as indicated. Wild-type or mutant TRs were then immunoprecipitated from postnuclear supernatants and analyzed on SDS-polyacrylamide gels (A) as described under MATERIALS AND METHODS. Dried gels were exposed to XAR film overnight (Kodak). Radioactivity in the bands was quantitated on a PhorphorImager (B). A representative experiment of four is shown.