Annexin D1 Promotes Potyvirus Infection through Interaction with Nuclear Inclusion Protein b and Ca2+-dependent Phosphorylation

Researchers at Shandong Agricultural University have made a groundbreaking discovery regarding the mechanisms of potyvirus infection in plants. According to their report, annexin D1, a calcium- and phospholipid-binding protein, plays a crucial role in the replication and systemic infection of potyviruses. The study found that annexin D1 interacts with nuclear inclusion protein b (NIb) of tobacco vein banding mosaic virus (TVBMV) and is recruited to the perinuclear region, where it co-localizes with the viral protein 6K2. Moreover, the researchers discovered that the interaction between annexin D1 and phosphokinase 29 (NbKIN29) is Ca2+-dependent and leads to the phosphorylation of annexin D1 at specific amino acid residues. This phosphorylation event is essential for the promotion of potyviral replication and systemic infection. The study's findings provide valuable insights into the molecular mechanisms underlying potyvirus infections and suggest potential avenues for the development of novel plant virus-resistant strategies.

Key Takeaways:

• Annexin D1 is a calcium- and phospholipid-binding protein that interacts with nuclear inclusion protein b (NIb) of tobacco vein banding mosaic virus (TVBMV) and is recruited to the perinuclear region.
• The interaction between annexin D1 and phosphokinase 29 (NbKIN29) is Ca2+-dependent and leads to the phosphorylation of annexin D1 at specific amino acid residues.
• Phosphorylation of annexin D1 is essential for the promotion of potyviral replication and systemic infection.
• The study suggests that annexin D1 positively regulates potyviral replication and systemic infection through its interaction with NIb.
• The findings of this study provide important insights into the molecular mechanisms underlying potyvirus infections and suggest potential avenues for the development of novel plant virus-resistant strategies.

Statistics:

• 3 amino acid residues (T204, T276, and S286) of annexin D1 are phosphorylated by NbKIN29.
• The interaction between annexin D1 and NIb is crucial for the recruitment of annexin D1 to the perinuclear region.
• Ca2+ ions play a vital role in the interaction between annexin D1 and NbKIN29, regulating the phosphorylation of annexin D1.
• The study's findings suggest that annexin D1 promotes potyviral replication and systemic infection in plants.

Sources:

• Xin-Yang Chen, et al. "Annexin D1 promotes potyvirus infection through interaction with nuclear inclusion protein b and Ca2+-dependent phosphorylation." Plant Physiology, 2025.
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• Elsevier - www.elsevier.com.
• Plant Physiology - www.journals.elsevier.com/plant-physiology-and-biochemistry/.