Figure 4

Identification and validation of putative oocyst/sporozoite-specific proteins (POSPs). (A) Comparison of the oocyst proteins identified in the present study with the expressed proteome of the tachyzoite and a dataset of proteomically identified proteins of sporulated M4 oocysts [25]. Numbers in brackets indicate the complexity of each dataset. The Venn diagram shows the presence in the VEG oocyst dataset of 154 proteins (POSPs), indicated by the asterisk, lacking proteomic evidence in tachyzoites. (B) Western blot analysis of total protein extracts from partially sporulated oocysts and tachyzoites of the VEG strain. The three panels show the reactivity of mouse polyclonal antibodies raised against three members of the POSP subset, i.e., the tyrosine-rich hypotetical protein TGME49_119890 and the LCCL domain-containing proteins TGME49_056040 and TGME49_067410. As quality and loading control, the tachyzoite lanes were also probed with an anti-SAG1 monoclonal antibody (arrowhead). O, oocyst; T, tachyzoite.