| Abstrakt: |
Mitogen-activated protein kinase (MAPK) cascades are important signaling modules in all organisms, which widely exist in plants. Mitogen-activated protein kinase kinase (MAPKKs) are located in the middle of the cascade reaction pathway and play the key roles in signal divergence. The disease resistance gene IbMAPKK9 was screened and cloned based on transcriptome data in sweetpotato, which contained a 987 bp open reading frame, encoding 328 amino acids and 1 domain (PF00069). Its protein mainly consisted of α-helixes and random coils. Multiple hormones (methyl jasmonate, ethylene, abscisic acid, gibberellin, and salicylic acid) and stress-related response elements were detected in the promoter region. Homologous protein comparison showed that IbMAPKK9 was closely related to ItMAPKK9-like (XP_031110493.1), InMAPKK9-like (XP_019189439.1), SlMAPKK9 (NP_001234595.1), and StMAPKK9 (XP_006363984.1). Besides, IbMAPKK9 gene encoded nuclear localization protein. The relative expression levels revealed that IbMAPKK9 was expressed in roots, stems, leaves, and petioles in response to Fusarium oxysporum f. sp batatas (Fob) infection. Transient expression analysis showed that IbMAPKK9 induced up-regulation of 5 genes related to salicylic acid synthesis pathway and signal transduction pathway within 48 hours, suggesting that IbMAPKK9 affected plant resistance by mediating salicylic acid signal pathway. This study can provide a theoretical basis for further analysis of the biological function of IbMAPKK9. [ABSTRACT FROM AUTHOR] |
