Arabidopsis thaliana: Model Organism in Plant Science and Biote
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Even people who are not plant scientists may have seen thale cress, an unassuming weed growing in sandy soils or even in the concrete gaps. Thale cress, or Arabidopsis thaliana native to Europe, Asia, and Africa, is the workhorse in the research field of plant genetics for decades as it was the first genome-sequenced plant in 2000.
Arabidopsis thaliana has become one of the most important model organisms in plant science and other biotechnological areas due to its short generation time, small size, easy growth, and the ability to produce prolific seeds through self-pollination. These advantages make it the lab rat of the plant world. Though having been studied for over 100 years, including attempts to grow it on the International Space Station and the Moon, scientists still are on the way to exploring this model plant.
Inspiring advancement comes from a Johns Hopkins University engineer co-led team. As previous genome sequencing of A. thaliana was unable to reach its centromeres, telomeres, and a few other complex regions of the genome, this team has sequenced Arabidopsis thaliana at a level of detail never previously achieved. This study recently published in Science has uncovered the secrets of the Arabidopsis centromeres, helping researchers understand the sequence, structure, and evolution of centromeres, and providing insights into a paradox that has mystified scientists for decades. Researchers who conducted this study hold that even though the research was in plants, it certainly has implications for human genetics, for example, understanding how human cells grow and divide so precisely.
Moreover, Arabidopsis allows researchers to gain more in-depth information on plant growth and development, which may also advance the genetic research of rice, corn, wheat, tomatoes, and beyond. Full genome sequences and detailed RNA and protein expression databases can elevate understanding of biological processes and functional studies of plants at cellular, tissue and organ levels, which is important for modeling multi-cellular systems. Confirmation of the actual localization and subcellular localization of key proteins would help refine these models.
Two of the most common bioinformatics approaches to investigate the localization of the proteins in Arabidopsis thaliana are using antibodies or protein fusions with fluorescent tags. Antibodies are powerful tools to locate proteins and have been widely used in western blot detection, enzyme-linked immunosorbent assays (ELISA), chromatin immunoprecipitation (ChIP), etc. For instance, the immunofluorescence microscopy technique for localization of Arabidopsis chloroplast proteins is performed with fluorescently labeled antibodies that are highly specific to chloroplast proteins. The Centre for Plant Integrative Biology (CPIB) has raised 94 Arabidopsis antibodies against root proteins for functional studies in plants. These antibodies would contribute to the understanding of expression, abundance and subcellular localization of key Arabidopsis root proteins in different mutant backgrounds as well as their role in root development.
By evaluating receptor proteins for major hormones that regulate plant growth and identifying how the hormone leads to the formation of protein complexes in the nucleus that translate signals into a specific gene expression response, researchers can find answers to some application areas of Arabidopsis genes through the forward genetics study. The future of Arabidopsis thaliana research is believed to be bright. With the gradual establishment of Arabidopsis thaliana as a model organism, continued breakthroughs would be achieved in the understanding of how plants work and how hormones regulate plant growth and development.