Figure 4.

Expression of Flowering-Related Genes in flk and Genetic Crosses.

(A) Transcript level analyses. The transcript levels were analyzed by RT-PCR–based DNA gel blot analyses. Note that FLC (bold) is upregulated, whereas FT and SOC1 (bold) are downregulated in flk. The other genes are not affected by the flk mutation.

(B) Genetic crosses. flk was genetically crossed with 35S∷CO and 35S∷FT, and homozygotic lines were obtained by segregation ratios and RT-PCR runs. 35S∷CO, a transgenic plant overexpressing CO; 35S∷FT, a transgenic plant overexpressing FT.

(C) FLK transcription in the mutants in the autonomous pathway. Thirty micrograms of total RNA was loaded onto each lane. C, Col-0; L, Landsberg erecta. The blot was probed with digoxigenin-UTP–labeled 18S rDNA as an RNA quality control.

(D) Comparison of FCA transcripts in flk and wild-type plants. Poly(A)⁺ RNA was isolated from total RNA, and 3 μg was loaded onto each lane.