Fig. 3. AtBRM expression pattern. (A) AtBRM mRNA expression in different tissues. RNA was isolated from adult plants grown in long days. Total RNA blots were hybridized first with an AtBRM probe and then reprobed with 18S ribosomal DNA (18S) as a loading control. Level of AtBRM mRNA was also determined by RT-PCR (bottom panel). (B) AtBRM protein expression in different tissues. 10 µg of nuclear protein were separated by SDS-PAGE, and subjected to western blotting using -AtBRMb antiserum. (C-H) Histochemical GUS staining of transgenic Arabidopsis plants containing an AtBRM promoter-first intron-GUS fusion (GUS staining is blue in whole mount, and pink when viewed with dark-field optics). (C) Ten-day-old whole seedling. Bar, 1 mm. (D) Magnification of a young leaf, showing staining of the vascular tissue. Bar, 1 mm. (E) Magnification of root tips of seedlings. Scale bar: 0.1 mm. (F) Inflorescence meristem. Scale bar: 0.1 mm. (G) Cross section of a vegetative shoot apical meristem, showing first leaves, leaf primordia and cotyledons. (H) Longitudinal section of floral bud at stage 12. Scale bar: 0.25 mm.