Endochitinase and beta-1,3-glucanase genes are developmentally regulated during somatic embryogenesis in Picea glauca.
Two cDNAs isolated from white spruce [Picea glauca (Moench) Voss] somatic embryos, are predicted to encode a basic class IV chitinase and a beta-1,3-glucanase, respectively corresponding to genes PgChi-1 and PgGlu-1. Each represents a multigene family in spruce. Transcripts homologous to PgChi-1 or PgGlu-1 genes were highly abundant in embryogenic tissues and gradually decreased after tissues were placed on abscisic acid-containing maturation medium, with lowest abundance in globular embryos. Transcripts related to PgGlu-1 became highly abundant again in early cotyledonary embryos but decreased thereafter, whereas transcripts related to PgChi-1 were also highly abundant in late cotyledonary embryos and plantlets in vitro; transcripts were either low (PgChi-1) or were not detectable (PgGlu-1) in needles. Wounding, drying and flooding stresses enhanced PgChi-1- and PgGlu-1-related gene expression. Fungal cell wall suspension enhanced PgGlu-1-related transcript accumulation, but reduced PgChi-1-related transcript abundance within 24 h. PgChi-1 and PgGlu-1 and their homologues may have roles in plant defense, and possibly developmental roles during spruce somatic embryo maturation.
Dong
J Z
JZ
Plant Biotechnology Institute, National Research Council of Canada, Saskatoon, Saskatchewan, Canada.
Dunstan
D I
DI
D000595:Amino Acid Sequence; D001483:Base Sequence; D002688:Chitinases / Q000235:genetics*; D018076:DNA, Complementary; D018744:DNA, Plant; D004777:Environment; D005656:Fungal Proteins / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D043326:Glucan 1,3-beta-Glucosidase; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D014197:Trees / Q000201:enzymology* / Q000235:genetics; D001617:beta-Glucosidase / Q000235:genetics*
D018076:DNA, Complementary; D018744:DNA, Plant; D005656:Fungal Proteins; D010940:Plant Proteins; D002688:Chitinases; C105807:endochitinase, spruce; D001617:beta-Glucosidase; D043326:Glucan 1,3-beta-Glucosidase