Study On Functional Characterization Of A Rice Lectin-like Receptor Kinase Gene (OsLecRK1)

OsLecRK1 is a hypothetical resistant-related gene that has been detected from rice genome based on the study of differentially expressed proteins from rice leaves in response to bacterial leaf streak (BLS). The cDNA length is 2361 bp, of which 2046 bp form the open reading frame encoding 681 amino acids. Lectin-like receptor kinases (LecRKs) and plant receptor-like kinases (RLKs) are specific functional group in a similar way. They are proteins with a predicted signal sequence, single transmembrane region, and cytoplasmic kinase domain. RLKs play an important part in plant in response to stress, incretion and pathogeny. LecRKs are a class of proteins originally described from Arabidopsis. They have a structure similar to other plant RLKs with an N-terminal targeting signal, a presumably extracellular domain, a single transmembrane (TM)-spanning helix, and a cytosolic kinase domain. All of above have led to suggestions that LecRKs could be involved in plant development and also adaptive processes such as wounding, defense, and protein storage. It remains enigmatic whether they have a major biochemical function leading to these different physiological roles.BLS caused by the pathogen Xanthomonas oryzae pv. Oryzicola (Xooc) is one of the major rice diseases in South China. It leads to decreased rice production generally by 40-60% in prevailing years. And genes which are related closely to resistance may be play important roles in controlling BLS epidemics and reducing economic losses.In this article, we describe our study of functional characterization of OsLecRK1 . Bioinformatic analysis suggests that the gene locates in the 7 chromosome. The cDNA and genomic sequences have been submitted to GenBank database (Accession No.: XM₄76511). Expression of the OsLecRK1 mRNA was demonstrated with Northern hybridization to be enhanced under BLS conditions.We specifically address the question of their potential role in relation to the resistance of plant study on the genetic transformation of OsLecRK1 in rice. First, a plant over expression vector according the cDNA of OsLecRK1 of rice and an RNAi expression vector of OsLecRK1 was constructed. Then, the OsLecRK1 gene and its RNAi fragment was integrated into the genome of rice callus via Agrobacterium tumefaciens EHA105 mediation respectively. The potential role of OsLecRK1 as resistant-related gene in the processes of defense is discussed.