Fig. 3.

Secretion profiles of MFS-associated variants of GFP-Fbn. (A) HEK293T cells were transfected with empty vector, pcDNA-GFPFbn, or constructs encoding the MFS-associated mutants (R2776X, L2780P, Y2849X, and Q2867X). Western blots were developed with an anti-GFP antibody. All MFS-associated variants were retained in the cells. (B) Western blots of cell fractions incubated with EndoH (E) showed a reduction in mass compared with untreated controls (C), indicating modification with simple sugars consistent with retention in the endoplasmic reticulum. (C) L2780 is in a region of high sequence conservation in the C-terminal propeptide. Species listed: human (Homo sapiens), mouse (Mus musculus), opossum (Monodelphis domestica), chicken (Gallus gallus), frog (Xenopus tropicalis), zebrafish (Danio rerio), lamprey (Petromyzon marinus), limpet (Lottia gigantea) water flea (Daphnia pulex) and jelly fish (Clytia hemisphaerica).