Co-expression of transcription factors ZmC1 and ZmR2 establishes an efficient and accurate haploid embryo identification system in maize.
Plant J
; 111(5): 1296-1307, 2022 09.
Article
en En
| MEDLINE
| ID: mdl-35793378
ABSTRACT
Because of their high efficiency during chromosome doubling, immature haploid maize (Zea mays L.) embryos are useful for doubled haploid production. The R1-nj marker is commonly used in doubled haploid breeding and has improved the efficiency of haploid identification. However, its effectiveness is limited by genetic background and environmental factors. We addressed this technical challenge by developing an efficient and accurate haploid embryo identification marker through co-expression of two transcription factor genes (ZmC1 and ZmR2) driven by the embryo-aleurone-specific bidirectional promoter PZmBD1 ; these factors can activate anthocyanin biosynthesis in the embryo and aleurone layer during early seed development. We developed a new haploid inducer, Maize Anthocyanin Gene InduCer 1 (MAGIC1), by introducing the transgenes into the haploid inducer line CAU6. MAGIC1 could identify haploids at 12 days after pollination, which is nine days earlier than CAU6. Importantly, MAGIC1 increased haploid identification accuracy to 99.1%, compared with 88.3% for CAU6. In addition, MAGIC1 could effectively overcome the inhibition of anthocyanin synthesis in some germplasms. Furthermore, an upgraded anthocyanin marker was developed from ZmC1 and ZmR2 to generate MAGIC2, which could identify haploids from diploids due to differential anthocyanin accumulation in immature embryos, coleoptiles, sheaths, roots, leaves, and dry seeds. This haploid identification system is more efficient and accurate than the conventional R1-nj-based method, and it simplifies the haploid identification process. Therefore, this system provides technical support for large-scale doubled haploid line production.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Zea mays
/
Antocianinas
Tipo de estudio:
Diagnostic_studies
/
Prognostic_studies
Idioma:
En
Revista:
Plant J
Asunto de la revista:
BIOLOGIA MOLECULAR
/
BOTANICA
Año:
2022
Tipo del documento:
Article
País de afiliación:
China