Poster: Salinity

Abs # 102: Screening for the interacting protein with Athb-12, an ABA-inducible homeodomain protein in Arabidopsis

Presenter:	Suh, Ji Yeon , c0331089@sookmyung.ac.kr
Authors	Suh, Ji Yeon  (A)   Cho, Hee-Yeon  (A)   Kim, Soo-Young  (C)   Hong, Chong-Chan  (B)   Cheon, Choong-Ill  (A)
Affiliations:	(A): Sookmyung Women's University (B): Kyeongsang National University (C): Kumho Life Sciences and Environmental Sciences

The Athb-12 gene is a homeobox gene and its amino acid sequence has a putative leucine zipper . It shares over 80% identity to the Arabidopsis Athb-7 in the HD-Zip motif. As the leucine zipper motif has been shown to be involved in protein-protein interaction, the interacting partner to Athb-12 was sought using a yeast two-hybrid library screening, and the ability of Athb-12 to form homo-/hetero-dimer was tested. Athb-12 did not form homodimer, as well as heterodimer with Athb-7. The libraries made from Arabidopsis flower and salt-induced Arabidopsis seedlings were used in this study. In each library screening, 1.1 x 10⁶ and 1.6 x 10⁶ clones were screened. Sequencing the positives revealed some cytoplasmic proteins, peroxisomal targeting signal type 1 receptor and catalase 3. One of the positive clones is a protein that has a nuclear localization signal, and a RING finger domain at the C-terminal region. This protein was named as Athb-12 interacting RING-finger protein (AIRP). The specific interaction of Athb-12 and AIRP was tested in yeast two-hybrid system and the expression pattern of the AIRP gene was compared with that of the Athb-12 gene by RT-PCR. Their binding is being tested in plants.