Figure 2.

Expression of xPR in Xenopus oocytes. (A) Total RNA (1 μg each) from oocytes of the various stages (stages I–III mixed with unknown ratio) were reverse-transcribed followed by PCR amplification using xPR primers encompassing exons E1 and E2. Lane 4 represents a negative control in which PCR was performed directly on input stage VI oocyte RNA without prior reverse transcription (RT). Shown is a representative of four independent experiments with arrows indicating the specifically amplified products. (B) Extracts from stage IV (lane 1), stage V (lane 2), or stage VI (lane 3) oocytes, isolated after collagenase treatment of ovarian tissues, or extracts from collagenase-treated and devitellinated oocytes (lane 4), were immunoblotted with anti-xPR. Equal amounts (50 μg) of proteins were loaded on each lane. The primary antibodies were visualized by incubation with appropriate secondary antibody-horseradish peroxidase conjugates followed by the use of a chemiluminescence kit (ECL, Amersham Pharmacia). Shown is a representative of three independent experiments. (C) Extracts from uninjected (lanes 1, 5, and 9) or Myc-xPR mRNA-injected (lanes 2, 6, and 10) oocytes (each representing half an oocyte), or extracts from untransfected (lanes 3, 7, and 11) or Myc-xPR-transfected (lanes 4, 8, and 12) COS cells (each representing one-tenth of a 3-cm dish) were immunoblotted with the indicated antibodies. Shown is a representative of three independent experiments.