Transcriptional stimulation via SC site of Bombyx sericin-1 gene through an interaction with a DNA binding protein SGF-3.
Three protein binding sites have been identified in the upstream region of the sericin-1 gene. Two of them, SA and SC sites, have been known as putative cis-acting elements. Using synthetic oligonucleotides of these binding sites, it was found that silk gland factor-1 (SGF-1) binds to the SA site, and silk gland factor-3 (SGF-3) binds to the SC site but not to a mutated SC site, SCM. Tissue distribution of the two factors was different. SGF-3 is present abundantly in the middle silk gland (MSG) where the sericin-1 gene is transcribed specifically but is also present in other cell types, though in a much less concentration. SGF-1 is observed very abundantly in the two parts of silk gland, MSG and posterior silk gland (PSG), but not in other cells. Templates containing multimerized SA or SC sites at -39 of the sericin-1 gene promoter were tested in MSG nuclear extracts. The SC multimer strongly activated transcription, while the mutant SCM multimer did not. The SA multimer also gave a slight stimulation of transcription. These results suggest that SGF-3 stimulates transcription through an interaction with the SC site, and SGF-1 does so weakly through the SA site.
Matsuno
K
K
Department of Developmental Biology, National Institute for Basic Biology, Okazaki, Japan.
Takiya
S
S
Hui
C C
CC
Suzuki
T
T
Fukuta
M
M
Ueno
K
K
Suzuki
Y
Y
D000818:Animals; D001483:Base Sequence; D012831:Bombyx / Q000235:genetics*; D002467:Cell Nucleus / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D005786:Gene Expression Regulation; D005796:Genes; D007700:Kinetics; D007814:Larva; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes; D010456:Peptides, Cyclic / Q000235:genetics*; D010957:Plasmids; D011401:Promoter Regions, Genetic; D047030:Sericins; D013698:Templates, Genetic; D014158:Transcription, Genetic
D004268:DNA-Binding Proteins; D015345:Oligonucleotide Probes; D010456:Peptides, Cyclic; D047030:Sericins