Figure 1.

Gene structure and expression levels of At4g35250 in wild-type and mutant seedlings. A, Structure of the gene HCF244. The HCF244 open reading frame (1,869 bp) consists of seven exons separated by six introns. The mutant allele hcf244 contains a T-DNA insertion at position +186, which is schematically marked by a triangle. Exons are shown in dark gray. B, Transcript analysis of HCF244. Five micrograms of total leaf RNA or the indicated dilutions, isolated from 2- to 3-week-old wild-type (WT), hcf244 mutant, and complemented hcf244 plants, were analyzed by RNA gel-blot hybridization using a radiolabeled probe against the HCF244 cDNA. The distribution of rRNAs was visualized by methylene blue staining. The degradation product of the 23S rRNA is indicated by an asterisk. C, Immunoblot analysis of the HCF244 protein. Thylakoid membrane proteins were isolated from wild-type and hcf244 leaves and separated by SDS-PAGE. Thirty micrograms of protein was loaded on the SDS gel. The detection of HCF244 was performed with the specific HCF244 antibody, whereas cytochrome f detection resulted from its heme-associated peroxidase activity. The position of cytochrome f is indicated by an asterisk.