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The expression of serine carboxypeptidases during maturation and germination of the barley grain.

ABSTRACT: cDNA clones encoding three additional serine carboxypeptidases (Ser-CPs) have been isolated from a gibberellic acid-induced barley aleurone cDNA library. The three deduced Ser-CPs belong to the two-chain subfamily of Ser-CPs; they are synthesized as precursors with a putative signal peptide, propeptide, and linker peptide between the A and B chains. Their identification provides the proof for the existence of more than three Ser-CPs in cereal grains, and, based on their sequences, they may exhibit new substrate specificities. The expression of these and of the three previously isolated Ser-CPs from barley grains (CP-MI, CP-MII, and CP-MIII) has been investigated by Northern and Western analysis and RNA PCR. CP-MII is the only Ser-CP to be expressed and accumulate in the developing grain and is stored in its active form in the mature grain. All six Ser-CPs are expressed de novo in the germinating grain, in the scutellum, and/or in the aleurone. Furthermore, at least CP-MI, CP-MII, and CP-MIII are secreted into the endosperm. In addition, all Ser-CPs (except CP-MI) are also expressed in the roots and shoots of the growing seedling. This enzyme family thus appears to be ubiquitous in the barley plant, which suggests that Ser-CPs play additional roles besides their participation in the mobilization of storage proteins.

SUBMITTER: Dal Degan F

PROVIDER: S-EPMC44575 | biostudies-other | 1994 Aug

REPOSITORIES: biostudies-other

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The expression of serine carboxypeptidases during maturation and germination of the barley grain.

Dal Degan F F Rocher A A Cameron-Mills V V von Wettstein D D

Proceedings of the National Academy of Sciences of the United States of America 19940801 17

cDNA clones encoding three additional serine carboxypeptidases (Ser-CPs) have been isolated from a gibberellic acid-induced barley aleurone cDNA library. The three deduced Ser-CPs belong to the two-chain subfamily of Ser-CPs; they are synthesized as precursors with a putative signal peptide, propeptide, and linker peptide between the A and B chains. Their identification provides the proof for the existence of more than three Ser-CPs in cereal grains, and, based on their sequences, they may exhib ...[more]

PMID: 7520177

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Dataset Information

The expression of serine carboxypeptidases during maturation and germination of the barley grain.

Publications

The expression of serine carboxypeptidases during maturation and germination of the barley grain.

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