Figure 3

Differential protein population of Zera-DsRed PBs. a) color of the different supernatants extracted from the initial PB sample purified on Iodixanol gradient. b) Tricine SDS-PAGE analysis of proteins sequentially extracted from purified Zera-DsRed PBs with Laëmmli buffer in the absence of reductant (S), in the presence of 100 mM DTT at room temperature (R) and in the presence of 100 mM DTT after heating at 95°C for 5 min. In each extraction step, samples were centrifuged at 15000 g and supernatants loaded in the gel. Arrow indicates Zera-DsRed protein. c) Western immunoassay of a total protein extract of tobacco leaves (1) and PB fraction (2) using anti BiP antibodies. Lane 3 is the control lane loaded with protein extract from non transformed leaves.