Expression of the OsPSK gene. (A) The steady state levels of OsPSK transcripts in rice Oc culture cells. Total RNAs (20 μg) extracted from Oc cells cultured for 3 (lane 1), 7 (lane 2), 10 (lane 3), or 14 days (lane 4) were separated by electrophoresis and hybridized with labeled cDNA (OsPSK) at 60°C. The blot was reprobed with the labeled rice actin cDNA (OsRAc1) to indicate equal loading of RNA. (B) OsPSK transcripts in transgenic Oc cells. Total RNAs (20 μg) were extracted from S2 sense (lane 1), A2 antisense (lane 2), or C1 control (lane 3) Oc cells cultured for 3 days and used to perform RNA blot analysis as described in A. (C) Expression of the OsPSK gene in rice seedlings. Total RNAs (1.5 μg) isolated from the first leaves (lane 1), second leaves (lane 2), shoot apexes (lane 3), crown roots (lane 4), and seminal roots (lane 5) of rice seedlings 8 days after germination were individually used to perform RT-PCR and visualized by hybridization as described above. A 0.5-kb band was predictably proliferated and hybridized with the labeled OsPSK cDNA at 65°C.