Legume-lectin receptor-like kinase required for normal pollen development and male fertility (PubMed:31833176, PubMed:32284546). Regulates pollen exine assembly and aperture development (PubMed:31833176, PubMed:32284546). Plays a critical role in annulus formation, and may participate in the formation of the fibrillar-granular layer underneath the operculum (PubMed:32284546). May function by regulating the expression of genes involved in pollen exine development (PubMed:31833176). Kinase activity is required for its function in pollen development (PubMed:31833176). ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Interacts with INP1 (PubMed:32284546). Interaction with INP1 is required for DAF1 polar localization at the future aperture sites in tetrads (PubMed:32284546). During meiosis, localizes diffusely in the cytosol and plasma membrane of microspore mother cells (MMCs). During tetrad development, localizes at the corners. At late tetrad stage, accumulates to the four corners of the tetrad, assembled into ring-like structures marking future aperture sites. When microspores are released from tetrads and preliminary aperture structures has formed, remains in a distinctly ring-shaped distribution beneath the aperture in the plasma membrane between the annulus and operculum. Expressed in roots, leaves, lemma, palea, pistil and anthers. Autophosphorylated at Thr-376; Ser-378; Thr-386; Thr-403 and Thr-657. Male sterility due to aborted pollen grains with abnormal exine an intine, and defective aperture (PubMed:32284546). Aborted pollen grains with defective apertures and intine formation, and male sterility (PubMed:32284546). In the N-terminal section; belongs to the leguminous lectin family. In the C-terminal section; belongs to the protein kinase superfamily. Ser/Thr protein kinase family. Extended N-terminus.