Figure 3.

RT-PCR analysis of AtEXP10 expression in selected Arabidopsis tissues. (A) Quantitative RT-PCR analysis of the RNA from young and old leaf blades and petioles, from pedicel abscission regions (AR, see Inset), and from the inflorescence stems (IS) subtending AR. The young blade and petiole are from the fifth leaf of 21-day-old plants and the old ones are from the fifth leaf of 35-day-old plants. AR and IS tissues were taken when the siliques were green (young) or yellow (old). Relative transcript abundance was calculated from the minimum number of cycles needed for detection of the amplified product on an ethidium bromide-stained gel. Amplification by 1.8-fold per cycle was assumed. The minimum number of cycles is shown on the right axis and is an average of two to four repeats. (B) RT-PCR results of RNA from the midrib (M) and the blade (B) tissues. Total RNA of each tissue was prepared from the eighth leaf of 27-day-old plants. The numbers indicate different RNA preparations. Primers for 18S rRNA (18S) were used for an internal loading standard in A and B. In B, the RT-PCR cycle numbers were 29 for AtEXP10 and 16 for 18S.