Identification and Molecular Characterisation of a Lectin Receptor-like Kinase (GhLecRK-2) from Cotton

Verticillium dahliae, the causative agent of Verticillium wilt, results in significant cotton (Gossypium hirsutum) crop losses worldwide. Identification of host genes involved in mounting an effective defence response may suggest targets for alternative control methods for this devastating fungus. In this study, the identification, cloning and characterisation of a V. dahliae elicitor-responsive lectin receptor-like kinase (GhLecRK-2) is described. Bioinformatic analysis of its deduced amino acid sequences revealed that GhLecRK-2 consists of an external legume-like lectin (L-lectin) domain, a single transmembrane spanning domain and a C-terminal Ser/Thr-specific protein kinase domain. In silico analysis of the promoter sequence revealed that it contains several defence-responsive regulatory elements. Expression analysis revealed that transcription of GhLecRK-2 is significantly up-regulated in response to treatment with a cell wall-derived V. dahliae fraction. The nature of the L-lectin domain suggests that GhLecRK-2 may be capable of interacting with the glycoconjugate-based fraction, and the enhanced transcription of GhLecRK-2 upon treatment with the cell wall extract suggests a role in perception and the activation of defence responses.