N-terminal region of rice polycomb group protein OsEZ1 is required for OsEZ1-OsFIE2 protein interaction

• Published in: Plant biotechnology reports Vol. 7; no. 4; pp. 503 - 510
• Main Authors: Na, Jong-Kuk, Seo, Mi-Hye, Moon, Seok-Jun, Yoon, In-Sun, Lee, Yeon-Hee, Kim, Jae Kwang, Lee, Kyun Oh, Kim, Dool-Yi
• Format: Journal Article
• Language: Korean
• Published: 2013
• Subjects: Seed development; OsEZ1; Polycomb group protein; Rice
• ISSN: 1863-5466; 1863-5474

Polycomb group (PcG) proteins form Polycomb Repressive Complex 2 (PRC2), which regulates seed development by the epigenetic control of gene expression. Interaction assay among Arabidopsis Fertilization-independent-seed2 (FIS) class PcG proteins showed that Fertilization- independent endosperm (FIE) interacts with Medea (MEA), a SET-domain polycomb protein, of which N-terminal region is crucial for the interaction. In this study, rice SET-domain PcG protein OsEZ1, also known as OsiEZ1 in indica rice, was analyzed to identify an interacting domain of OsEZ1 required for OsEZ1-OsFIE2 protein interaction. A series of OsEZ1 deletions were generated and used to determine an interacting domain of OsEZ1 with OsFIE2 using the yeast two-hybrid system. Among OsEZ1 deletions, only OsEZ1D2 and OsEZ1D3 interacted with OsFIE2, indicating that the 155K-169R or N-proximal region of OsEZ1 is crucial for OsFIE2-OsEZ1 interaction. To examine the physiological roles of OsEZ1, 35S:OsEZ1 Arabidopsis lines were generated. OsEZ1 overexpressors exhibited altered seedling growth and seed size, implying that OsEZ1 may play important roles in seedling and seed development.