Promoter of the POU-M1/SGF-3 gene involved in the expression of Bombyx silk genes.
To characterize the transcription regulation of the POU-M1/SGF-3 gene, we have cloned a genomic DNA fragment encompassing the whole coding region and its flanking sequences. This gene does not contain any intron. The 5'-flanking region of the gene contains several interesting motifs, such as homeodomain-binding motifs, sequences resembling the transcriptional factor Sp1-binding site, and TGTTT motifs, but lacks some of the typical transcriptional regulatory sequences, such as TATA and CCAAT boxes. Transcriptional analysis of a series of deletion mutants of the gene in the nuclear extracts prepared from the middle silk gland of 2-day-old fifth instar larvae revealed the presence of multiple cis-regulatory elements located both upstream and downstream of the initiation site. One of these elements, the homeodomain-binding element, was identified to mediate negative regulation. By mobility shift assay using the POU-M1 specific antibodies, we found that this negative element interacts with the POU-M1/SGF-3. Transcription analysis in vitro using templates mutagenized in the PB region and one of the POU-M1 antibodies indicated that the PB region is an autoregulatory element responsible for SGF-3-dependent transcriptional repression.
Xu
P X
PX
National Institute for Basic Biology, Okazaki, Japan.
Fukuta
M
M
Takiya
S
S
Matsuno
K
K
Xu
X
X
Suzuki
Y
Y
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D015139:Blotting, Southern; D012831:Bombyx / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D017931:DNA Primers; D018076:DNA, Complementary / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics*; D005091:Exons; D005786:Gene Expression Regulation; D017344:Genes, Insect; D015698:Genomic Library; D019476:Insect Proteins; D007438:Introns; D007814:Larva; D008969:Molecular Sequence Data; D016296:Mutagenesis; D016297:Mutagenesis, Site-Directed; D050809:POU Domain Factors; D011401:Promoter Regions, Genetic; D011506:Proteins / Q000235:genetics*; D012045:Regulatory Sequences, Nucleic Acid; D015183:Restriction Mapping; D017384:Sequence Deletion; D047011:Silk; D013698:Templates, Genetic; D014157:Transcription Factors / Q000235:genetics*; D014158:Transcription, Genetic
D017931:DNA Primers; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D019476:Insect Proteins; D050809:POU Domain Factors; C085604:POU-M1 protein, Bombyx mori; D011506:Proteins; D047011:Silk; D014157:Transcription Factors