Abstract:The gene for the large subunit of ribulose 1,5-bisphosphate carboxylase in rice(Oryza sativa L., ssp. indica) has been cloned using M13mpl8/19-JM101 and pUC118/l19-MVl184 systems. After subcloning and construction of a series of unidirectional deletions, the nucleotide sequence was determined by the dideoxychain termination method. The structure gene encompasses 1434, which encodes 477 amino acids. The two subspecies of rice, i.e. japonica and indica have only one diverse nucleotide, which is located in the third site of a codon and does not change the kind of amino acids. The promoter region of rbcL gene is closely contiguous to that of atpB gene in its 5′-terminal upstream of rbcL gene. A repetitive sequence homologous to a part of rp123 gene exists in the 3′-terminal downstream of rbcL gene. With the aid of computer, we have compared the sequence of rbcL gene in rice with those in other species determined so far to investigate the phylogenetic topologies.