Arabidopsis thaliana: a model plant for genetics and molecular biology

Key characteristics

Arabidopsis is a rosette-forming herb with small white flowers and a lifecycle that can be completed in about six weeks under laboratory conditions. It has five chromosomes and a relatively small nuclear genome (~125 million base pairs), which contributed to it becoming the first plant to have its complete sequence published in 2000 by the Arabidopsis Genome Initiative (first plant genome). The species is predominantly self-fertilizing but can outcross, and produces large numbers of tiny seeds that are easy to store and handle.

• Family: Brassicaceae — related to cultivated species such as cabbage and radish.
• Genome: compact, well-annotated; maintained by resources such as TAIR and other databases.
• Genes and proteins: studies refer to roughly ~27,000 genes and tens of thousands of predicted proteins (~35,000 proteins), numbers that change as annotation improves.

History and development as a model

Interest in Arabidopsis among geneticists began in the mid-20th century because it could be grown easily in small space and produced many offspring. Its adoption accelerated with the development of molecular tools and the establishment of community resources. The completed genome sequence in 2000 created a foundation for functional genomics, mutant collections and comparative studies. Centralized databases and seed stock centers helped standardize strains and share reagents across laboratories.

Research uses and experimental advantages

Arabidopsis is used to investigate fundamental processes such as gene regulation, development, signal transduction and responses to the environment. It has been instrumental in dissecting the genetic control of flower development, hormone signalling, immunity and circadian rhythms. Work on light perception and photoreceptor-mediated pathways is frequently illustrated by studies of light sensing in Arabidopsis. Its small size, rapid life cycle and the availability of efficient transformation methods (for example Agrobacterium-mediated transfer) make it well suited for both forward and reverse genetics.

Tools, resources and notable facts

The research community has developed extensive resources: T-DNA insertion libraries, mutant screens, genome-wide expression data and curated annotation accessible through repositories and informational portals (molecular biology resources). Arabidopsis serves as a reference for comparative genomics across plants and helps translate discoveries into crop research. Because it is closely related to agriculturally important brassicas, insights often inform breeding and biotechnology in related species.

Importance and distinctions

While Arabidopsis is not a crop species, its role as a tractable experimental system makes it indispensable for basic plant science. Its adoption demonstrates how a single well-characterized organism can accelerate an entire field: studies built on Arabidopsis findings continue to impact understanding of plant growth, development and stress responses. For broader context and further reading see community pages on genetics and plant science (plant genetics, model organism, and other entries such as distribution and genome resources at sequencing initiatives).

Researchers and students encountering Arabidopsis will find a mature toolkit, curated datasets and an active community; these attributes keep it at the forefront of experimental plant biology and genomics.