cDNA cloning, primary structure, and in vitro biosynthesis of the DB58 lectin from Dolichos biflorus.
Previous studies have shown that the Dolichos biflorus plant contains a lectin in its stems and leaves, called DB58, that is closely related to the D. biflorus seed lectin. DB58 is a heterodimer composed of two closely related subunits. Immunoprecipitation of total translation products from D. biflorus stem and leaf mRNA suggests a single polypeptide precursor for both of these subunits. Several identical cDNA clones representing the entire coding region of the DB58 mRNA have been isolated from a D. biflorus stem and leaf cDNA library. The DB58 cDNA represents an mRNA encoding a polypeptide of Mr = 29,545. The predicted polypeptide is equal in length to the larger subunit of DB58 with the addition of a 22-amino acid amino-terminal signal sequence. The sequence of the DB58 lectin exhibits 84% homology to the D. biflorus seed lectin at the amino acid level, suggesting that these lectins are encoded by differentially expressed genes and may have evolved to carry out tissue-specific functions. Comparison of the DB58 sequence to other leguminous seed lectins indicates a high degree of structural conservation.
Schnell
D J
DJ
Department of Biochemistry and Biophysics, University of California, Davis 95616.
Etzler
M E
ME
D000595:Amino Acid Sequence; D001483:Base Sequence; D015152:Blotting, Northern; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics* / Q000302:isolation & purification; D004262:DNA Restriction Enzymes; D005796:Genes; D037102:Lectins / Q000096:biosynthesis / Q000235:genetics*; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D009710:Nucleotide Mapping; D037121:Plant Lectins; D010944:Plants / Q000235:genetics* / Q000378:metabolism; D014176:Protein Biosynthesis; D012333:RNA, Messenger; D014158:Transcription, Genetic
D037102:Lectins; D037121:Plant Lectins; D012333:RNA, Messenger; C036554:dolichos biflorus agglutinin; D004247:DNA; D004262:DNA Restriction Enzymes