Electronic Thesis and Dissertation Repository


Master of Science




Lining Tian

2nd Supervisor

Denis Maxwell

Joint Supervisor


Histone deacetylases have important roles in development and stress response in plants. To further investigate their function, the HD2D gene, of the plant specific HD2 family, was studied. An hd2d-1 mutant and two HD2D overexpression lines were used in this study. Germination was delayed in hd2d-1 and HD2D overexpression seeds only in the presence of ABA. HD2D was found to positively regulate the expression of members of the ABA-response pathway (ABI1, ABI5, and RD29A) leading to increased resistance to drought and salinity treatments. Furthermore, HD2D expression delayed flowering by positively regulating FLC expression. Using bimolecular fluorescence complementation, the HD2D protein was found to interact with the ABA pathway members ABI1, ABI2, and ABI5. Taken together, the results of this study suggest that HD2D is a regulator of ABA responses in Arabidopsis. By expanding the knowledge of plant stress response, this research will help lead to long-term improvements of drought tolerance.