Characterization of two soybean repetitive proline-rich proteins and a cognate cDNA from germinated axes.
We have resolved and analyzed two proline-rich proteins isolated from the walls of soybean cells in culture. The proteins are similar in amino acid content, containing 20% proline, 20% hydroxyproline, 20% lysine, 16% valine, 10% tyrosine, and 10% glutamate. The proteins undergo a rearrangement or a limited cleavage in dilute NaOH, but are otherwise remarkably stable to a high concentration of alkali. We have cloned and sequenced a cDNA from soybean axes germinated for 31 hours (1A10-2) coding for a protein that closely corresponds in its amino acid content to that of the proline-rich proteins. The cDNA sequence predicts a decameric repeat of Pro-Pro-Val-Tyr-Lys-Pro-Pro-Val-Glu-Lys. Consequently, this class of proteins is referred to as repetitive proline-rich proteins, i.e., RPRP2 and RPRP3. We have also analyzed RNA gel blots with probes that discriminate between the new cDNA clone and a related cDNA previously reported [SbPRP1; Hong, Nagao, and Key (1987). J. Biol. Chem. 262, 8367-8376]. Messenger RNAs from young seedlings and from soybean suspension cultures correspond primarily to the new RPRP clone (1A10-2), whereas the predominant mRNA accumulating later in the roots corresponds to SbPRP1.
Datta
K
K
Institute for Cancer Research, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111.
Schmidt
A
A
Marcus
A
A
D000595:Amino Acid Sequence; D002851:Chromatography, High Pressure Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D008969:Molecular Sequence Data; D009928:Organ Specificity / Q000235:genetics; D010455:Peptides / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D055232:Proline-Rich Protein Domains; D013025:Glycine max / Q000235:genetics* / Q000254:growth & development
D010455:Peptides; D010940:Plant Proteins