The relationship between ß-amylase and the degradation of starch temporarily stored in rice leaf blades.
Biosci Biotechnol Biochem
; 87(7): 736-741, 2023 Jun 23.
Article
em En
| MEDLINE
| ID: mdl-37142417
ABSTRACT
Starch is stored temporarily in the leaves during the day but degraded during the night. In this study, we investigated the relationship between diurnal changes in starch content in rice leaf blades and the mRNA levels of ß-amylase genes. In addition to the known plastid-type ß-amylases OsBAM2 and OsBAM3, OsBAM4, and OsBAM5 were also identified as plastid targeted proteins. In the leaf blades, starch contents, which reached its maximum at the end of day, showed two periods of marked decrease from 1800 to 2100 and from 2400 to 600. The expression of OsBAM2, OsBAM3, OsBAM4, and OsBAM5 was maintained at a low level from 1800 to 2100 but increased strongly after midnight. Furthermore, ß-amylase activity gradually increased after 2100, reaching a maximum during the early morning. These results suggest that in rice leaf blades, ß-amylase plays an important role in starch degradation by being highly active from midnight to dawn.
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Base de dados:
MEDLINE
Assunto principal:
Oryza
/
Beta-Amilase
Idioma:
En
Ano de publicação:
2023
Tipo de documento:
Article