Expression of the BnmNAP subfamily of napin genes coincides with the induction of Brassica microspore embryogenesis

• Published in: Plant molecular biology Vol. 26; no. 6; p. 1711
• Main Authors: Boutilier, K.A. (Ottawa Univ., Ottawa, Ont. (Canada). Dept. of Biology), Gines, M.J, DeMoor, J.M, Huang, B, Baszczynski, C.L, Iyer, V.N, Miki, B.L
• Format: Journal Article
• Language: English
• Published: Netherlands 01.12.1994
• Subjects: 2S Albumins, Plant; Base Sequence; Brassica - embryology; Brassica - genetics; BRASSICA NAPUS; Cells, Cultured; DESARROLLO EMBRIONARIO; DEVELOPPEMENT EMBRYONNAIRE; DNA, Complementary - genetics; EMBRYONIC DEVELOPMENT; EXPRESION GENICA; EXPRESSION DES GENES; GENE EXPRESSION; Gene Library; Genes, Plant - genetics; Genetic Vectors; Germ Cells; Glucuronidase - biosynthesis; Glucuronidase - genetics; Haploidy; Molecular Sequence Data; Multigene Family - genetics; Oligonucleotide Probes; Plant Proteins - biosynthesis; Plant Proteins - genetics; Pollen - growth & development; PROTEINAS DE RESERVA; PROTEINE DE RESERVE; Recombinant Fusion Proteins - biosynthesis; Sequence Homology, Nucleic Acid; STORAGE PROTEINS; Transformation, Genetic
• ISSN: 0167-4412; 1573-5028
• DOI: 10.1007/BF00019486

Brassica napus cv. Topas microspores can be diverted from pollen development toward haploid embryo formation in culture by subjecting them to a heat stress treatment. We show that this switch in developmental pathways is accompanied by the induction of high levels of napin seed storage protein gene expression. Changes in the plant growth or microspore culture conditions were not by themselves sufficient to induce napin gene expression. Specific members of the napin multigene family were cloned from a cDNA library prepared from microspores that had been induced to undergo embryogenesis. The majority of napin clones represented three members (BnmNAP2, BnmNAP3 and BnmNAP4) that, along with a previously isolated napin genomic clone (BngNAP1), constitute the highly conserved BnmNAP subfamily of napin genes. Both RNA gel blot analysis, using a subfamily-specific probe, and histochemical analysis of transgenic plants expressing a BngNAP1 promoter-beta-glucuronidase gene fusion demonstrated that the BnmNAP subfamily is expressed in embryogenic microspores as well as during subsequent stages of microsporic embryo development.