Analysis of the promoter region of napin genes from Brassica napus demonstrates binding of nuclear protein in vitro to a conserved sequence motif.
Napin is a seed storage protein from Brassica napus (rape) that is encoded by a gene family. We have isolated and characterized a novel napin gene, napB. Comparisons of the 5'-upstream region of napB to the promoter regions of previously published napin genes reveal that certain sequence motives are evolutionary conserved and may be implicated in gene regulation. These consensus motives, that overlap with purine/pyrimidine stretches, are TACACAT and CATGCA both of which frequently occur as overlapping, direct repeats. Related or identical sequences are also found in the upstream regions of the homologous genes of Arabidopsis thaliana. One copy of the CATGCA motif occurs in close proximity to the TATA box in all the above genes. In this case it overlaps with an octamer sequence (ATGCAAAT) which is a sequence element common in many eukaryotic promoters and enhancers. The TACACAT sequence, as part of a longer purine/pyrimidine stretch, was found to interact with a protein present in crude nuclear extracts from developing B. napus seeds. Napin genes appear to be methylated to almost equal extents whether present in expressing or non-expressing tissue.
Ericson
M L
ML
Department of Cell Research, Uppsala Biomedical Center, Swedish University of Agricultural Sciences.
Murén
E
E
Gustavsson
H O
HO
Josefsson
L G
LG
Rask
L
L
D055516:2S Albumins, Plant; D000595:Amino Acid Sequence; D001483:Base Sequence; D001937:Brassica / Q000235:genetics*; D004247:DNA / Q000378:metabolism; D008745:Methylation; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics*; D011401:Promoter Regions, Genetic; D012091:Repetitive Sequences, Nucleic Acid
D055516:2S Albumins, Plant; D009687:Nuclear Proteins; D010940:Plant Proteins; C050363:napin protein, Brassica napus; D004247:DNA