T-DNA insertion mutants of Arabidopsis DA1 orthologous genes displayed altered plant height and yield-related traits in rice (O. sativa L.)

Authors: SHIM, KYU-CHAN - Chungnam National University; LUONG, NGOC HA - Chungnam National University; Tai, Thomas; LEE, GYU-RI - Chungnam National University; AHN, SANG-NAG - Chungnam National University; PARK, INKYU - Changwon National University

Submitted to: Genes and Genomics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/1/2024
Publication Date: 3/4/2024
Citation: Shim, K., Luong, N., Tai, T., Lee, G., Ahn, S., Park, I. 2024. T-DNA insertion mutants of Arabidopsis DA1 orthologous genes displayed altered plant height and yield-related traits in rice (O. sativa L.). Genes and Genomics. 46:451-459. https://doi.org/10.1007/s13258-024-01501-1.
DOI: https://doi.org/10.1007/s13258-024-01501-1

Interpretive Summary: Grain size is a major determinant of yield in rice. The ubiquitin proteasome pathway plays an important role in controlling grain size based on studies of the Arabidopsis thaliana ubiquitin receptor DA1 gene. To examine the influence of DA1 orthologues on rice agronomic traits, homozygous T-DNA insertion mutants in rice DA1, HDR3, and HDR3.1 and the DA1 interacting gene GW2 were isolated. These mutants were evaluated for various productivity traits including plant height, tiller number, flowering time, and grain dimensions (length, width, and weight). Significant differences in some of these traits were identified between the mutants and their corresponding wild type variety Dongjin, which indicates that these genes also play an important part in growth and development in rice and may be useful targets for breeding strategies aimed at increasing productivity.

Technical Abstract: The Arabidopsis DA1 gene plays an important role in organ and seed development. In this study, the function of orthologous genes of Arabidopsis DA1 in rice was investigated by analyzing T-DNA insertion mutants of DA1, HDR3, HDR3.1, and the DA2 ortholog GW2. The T-DNA insertion locations were confirmed by PCR, and homozygous plants were evaluated for agronomic traits, including plant height, tiller number, days to heading, and grain size. The results showed that hdr3 and hdr3.1 had significantly shorter plant height and smaller grain size, while gw2 and da1 lines displayed significantly increased plant height and grain size compared to the wild type variety Dongjin. Leaf senescence assays indicated that hdr3 displayed delayed leaf senescence, while hdr3.1 showed slightly earlier leaf senescence under dark incubation. These findings suggest that DA1 orthologous genes in rice play important roles in regulating plant growth and development and could be targets for crop improvement.