FLS2

FLS2, also known as FLS2.1, is a gene that plays a crucial role in plant development and response to environmental stimuli. It is a member of the F-box/Leucine-rich repeat (FBL) family of genes, which are involved in various biological processes, including cell cycle regulation, protein degradation, and stress response.

The FLS2 gene encodes a protein that functions as a receptor-like kinase, which is a type of protein that can bind to specific ligands and initiate signaling pathways in response to external stimuli. FLS2 is known to interact with the FLS2.2 protein, forming a heterodimer that acts as a receptor for the bacterial effector protein, HrcX, produced by the plant pathogen Xanthomonas campestris pv. campestris (Xcc).

The FLS2-FLS2.2 complex is a key component of the plant immune response to bacterial pathogens. Upon recognition of HrcX, the FLS2-FLS2.2 complex activates a signaling cascade that leads to the activation of defense-related genes and the production of antimicrobial compounds. This response is essential for the plant's ability to resist infection and maintain its health.

Mutations in the FLS2 gene have been shown to confer resistance to Xcc in several plant species, including Arabidopsis thaliana and tomato. This resistance is due to the inability of the mutated FLS2 protein to form a functional complex with FLS2.2, resulting in a loss of HrcX recognition and subsequent immune response.

In summary, FLS2 is a critical gene in plant immunity, encoding a receptor-like kinase that forms a complex with FLS2.2 to recognize and respond to bacterial pathogens. Mutations in FLS2 can confer resistance to specific pathogens, highlighting its importance in plant defense mechanisms.