receptorlike

Receptorlike is an adjective used in molecular biology to describe proteins or molecules that resemble cell-surface receptors in structure or function, and that participate in the perception of external signals. The term is applied across organisms to denote proteins that mediate signal reception and transduction, often as part of larger receptor families.

In plants, receptor-like kinases and receptor-like proteins form major families. Receptor-like kinases are transmembrane proteins with an extracellular ligand-binding domain, a single transmembrane helix, and an intracellular kinase domain that relays signals by phosphorylation. They perceive peptide ligands, hormones, or pathogen-associated molecular patterns and trigger immune responses or developmental programs. Examples include FLS2, which detects bacterial flagellin, the brassinosteroid receptor BRI1, and EFR, which recognizes elongation factor Tu.

Receptor-like proteins share the extracellular ligand-binding domain and membrane anchoring but lack a cytoplasmic kinase domain. They often function in complex with kinases to transduce signals. In plants, RLPs contribute to immune recognition by forming receptor complexes with co-receptors, enabling specific defense responses.

In animals and other organisms, receptorlike proteins may adopt architectures similar to receptors yet lack traditional signaling domains. They can act as decoys, modulators, or co-receptors, shaping signaling networks without singular enzymatic activity and sometimes influencing development or immunity indirectly.

Receptorlike proteins are the subject of ongoing research due to their roles in development, immunity, and environmental responses. Understanding their domain structures, ligands, and interaction partners helps in fields such as crop improvement, neurobiology, and biomedical signal transduction.