Mutation in a chlorophyll-binding motif of Brassica ferrochelatase enhances both heme and chlorophyll biosynthesis.
Cell Rep
; 41(10): 111758, 2022 12 06.
Article
en En
| MEDLINE
| ID: mdl-36476857
ABSTRACT
The heme branch of tetrapyrrole biosynthesis contributes to the regulation of chlorophyll levels. However, the mechanism underlying the balance between chlorophyll and heme synthesis remains elusive. Here, we identify a dark green leaf mutant, dg, from an ethyl methanesulfonate (EMS)-induced mutant library of Chinese cabbage. The dg phenotype is caused by an amino acid substitution in the conserved chlorophyll a/b-binding motif (CAB) of ferrochelatase 2 (BrFC2). This mutation increases the formation of BrFC2 homodimer to promote heme production. Moreover, wild-type BrFC2 and dBrFC2 interact with protochlorophyllide (Pchlide) oxidoreductase B1 and B2 (BrPORB1 and BrPORB2), and dBrFC2 exhibits higher binding ability to substrate Pchlide, thereby promoting BrPORBs-catalyzed production of chlorophyllide (Chlide), which can be directly converted into chlorophyll. Our results show that dBrFC2 is a gain-of-function mutation contributing to balancing heme and chlorophyll synthesis via a regulatory mechanism in which dBrFC2 promotes BrPORB enzymatic reaction to enhance chlorophyll synthesis.
Palabras clave
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Brassica
/
Ferroquelatasa
Idioma:
En
Revista:
Cell Rep
Año:
2022
Tipo del documento:
Article
País de afiliación:
China