Yic. Hsing et al., TISSUE-SPECIFIC AND STAGE-SPECIFIC EXPRESSION OF A SOYBEAN (GLYCINE-MAX L.) SEED-MATURATION, BIOTINYLATED PROTEIN, Plant molecular biology, 38(3), 1998, pp. 481-490
A cDNA clone GmPM4 which encodes mRNA species in mature or dry soybean
seeds was characterized. DNA sequence analysis shows that the deduced
polypeptides have a molecular mass of 68 kDa. GmPM4 proteins have a r
elatively high amino acid sequence homology with a major biotinylated
protein isolated from pea seeds, SBP65, but both of these proteins dif
fer markedly from that of presently known biotin enzymes. The accumula
tion of GmPM4 mRNA is detectable in the leaf primodium and the vascula
r tissues of the hypocotyl-radicle axis of mature seeds, and the GmPM4
proteins are present at high levels in dry and mature soybean seeds,
but not in fresh immature seeds. It degrades rapidly at the early stag
e of seed germination. These proteins are boiling-soluble and biotinyl
ated when they are present endogenously in soybean seeds; however, the
same recombinant protein expressed in Escherichia coli is boiling-sol
uble, but it is not biotinylated.