English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Heme is involved in various biological processes as a cofactor of hemoproteins located in various organelles. In plant cells, heme is synthesized by two isoforms of plastid-localized ferrochelatase, FC1 and FC2. In this study, by characterizing  Arabidopsis  T-DNA insertional mutants, we showed that the allocation of heme is differentially regulated by ferrochelatase isoforms in plant cells. Analyses of weak ( fc1-1 ) and null ( fc1-2 ) mutants suggest that FC1-producing heme is required for initial growth of seedling development. In contrast, weak ( fc2-1 ) and null ( fc2-2 ) mutants of  FC2  showed pale green leaves and retarded growth, indicating that FC2-producing heme is necessary for chloroplast development. During the initial growth stage,  FC2  deficiency caused reduction of plastid cytochromes. In addition, although  FC2  deficiency marginally affected the assembly of photosynthetic reaction center complexes, it caused relatively larger but insufficient light-harvesting antenna to reaction centers, resulting in lower efficiency of photosynthesis. In the later vegetative growth, however,  fc2-2  recovered photosynthetic growth, showing that FC1-producing heme may complement the  FC2  deficiency. On the other hand, reduced level of cytochromes in microsomal fraction was discovered in  fc1-1 , suggesting that FC1-producing heme is mainly allocated to extraplastidic organelles. Furthermore, the expression of  FC1  is induced by the treatment of an elicitor flg22 while that of  FC2  was reduced, and  fc1-1  abolished the flg22-dependent induction of  FC1  expression and peroxidase activity. Consequently, our results clarified that FC2 produces heme for the photosynthetic machinery in the chloroplast, while FC1 is the housekeeping enzyme providing heme cofactor to the entire cell. In addition, FC1 can partly complement FC2 deficiency and is also involved in defense against stressful conditions.

Allocation of Heme Is Differentially Regulated by Ferrochelatase Isoforms in Arabidopsis Cells