Glycinin A5A4B3 mRNA: cDNA cloning and nucleotide sequencing of a splitting storage protein subunit of soybean.
The complete nucleotide sequence of a cloned cDNA, designated pGA5A4B3822, corresponding to glycinin A5A4B3 mRNA was determined. Analysis of the cDNA insert revealed that it contained 1899 nucleotides of mRNA sequence with a 5'-terminal non-translated region of 31 nucleotides, a signal peptide region corresponding to 23 amino acids, an acidic subunit region (A5) corresponding to 97 amino acids, an acidic subunit region (A4) corresponding to 257 amino acids followed by a basic subunit region (B3) corresponding to 185 amino acids, and a 3'-terminal non-translated region of 182 nucleotides. These results show that the glycinin A4 subunit, which is not found to be linked to a basic subunit via a disulfide bond, is synthesized as a full-sized precursor, i.e. the A5A4B3 subunit complex, from a single mRNA, followed by post-translational processing to generate an intermediary subunit complex (A5-B3), covalently linked by a disulfide bond, and the mature A4 subunit, which may associate with the above subunit complex by non-covalent interactions. From the results obtained by the Chou-Fasman rules we speculated that the two post-translational cleavage sites of this subunit precursor might be processed by the same proteolytic enzyme.
Momma
T
T
Negoro
T
T
Hirano
H
H
Matsumoto
A
A
Udaka
K
K
Fukazawa
C
C
D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D004247:DNA; D004251:DNA Transposable Elements; D005916:Globulins / Q000032:analysis* / Q000235:genetics; D010940:Plant Proteins / Q000032:analysis* / Q000235:genetics; D011498:Protein Precursors / Q000032:analysis* / Q000235:genetics; D011499:Protein Processing, Post-Translational; D012333:RNA, Messenger / Q000032:analysis / Q000502:physiology; D030262:Soybean Proteins; D013025:Glycine max / Q000032:analysis; D014158:Transcription, Genetic
D004251:DNA Transposable Elements; D005916:Globulins; D010940:Plant Proteins; D011498:Protein Precursors; D012333:RNA, Messenger; D030262:Soybean Proteins; D004247:DNA; C011474:glycinin