Proteome Analysis of the Specific Proteins From Japanese Birch Callus Infected With a Canker‐Rot Fungus <i>Inonotus Obliquus</i> Strain <scp>IO</scp> ‐ <scp>U1</scp> ( <scp>NBRC</scp> 113406)

ABSTRACT The specific proteins from Japanese birch ( Betula platyphylla var. japonica plantlet No. 8) callus infected with a canker‐rot fungus Inonotus obliquus strain IO‐U1 (NBRC 113406) at the early infection stage were identified using proteome analysis. The intact, wounded, and infected calli were prepared, and the protein samples obtained at 2 days post‐treatments were subjected to two‐dimensional electrophoresis (2‐DE) for detecting infection‐specific proteins. The infection‐specific proteins were then analysed using LC/MS/MS, and the obtained data were subjected to the NCBIprot database for identifying the proteins based on homologous sequences search. A total of 134 protein spots on the 2‐DE gel were detected as infection‐specific proteins. Of these spots, 10 highly expressed proteins were identified as protochlorophyllide reductase chloroplastic (spot ID 1564), enolase (spot ID 368), mitochondrial‐processing peptidase subunit alpha‐like (spot ID 441), mitochondrial‐processing peptidase subunit alpha isoform B (spot ID 1578), T‐complex protein 1 subunit eta (spot ID 356), glutathione S ‐transferase‐like protein (spot ID 1121), glutathione S ‐transferase‐like protein, partial (spot ID 1527), protein WALLS ARE THIN 1‐like (spot ID 1444), and 1 Sc‐3 (spot IDs 1290 and 1322). The obtained results suggest that Japanese birch callus is capable of inducing several proteins related to photosynthesis, energy production, protein import machinery in mitochondria, protein folding, detoxification, secondary cell wall formation, and PR‐10 protein at the early infection stage as responses to defend itself against I. obliquus strain IO‐U1 infection.