Molecular cloning and characterization of SRAM, a novel insect rel/ankyrin-family protein present in nuclei.
Previously, we purified a 59-kDa protein that binds to the kappaB motif of the Sarcophaga lectin gene. Here we report its cDNA cloning and some of its characteristics as a novel member of the Rel/Ankyrin-family. This protein, named SRAM, contained a Rel homology domain, a nuclear localization signal and 4 ankyrin repeats, but lacked the Ser-rich domain and PEST sequence that Relish contained. We found that SRAM was localized in the nuclei of NIH-Sape-4 cells, which are an embryonic cell line of Sarcophaga. The Sarcophaga lectin gene promoter containing tandem repeats of the kappaB motifs was activated in NIH-Sape-4 cells. In Drosophila mbn-2 cells, Dif alone activated this reporter gene and a cooperative effect was detected when SRAM and Dif were co-transfected, although SRAM alone did not activate it. This is the first report of a Rel/Ankyrin molecule that exists in the nuclei.
Shiraishi
H
H
Department of Cell Biochemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan.
Kobayashi
A
A
Sakamoto
Y
Y
Nonaka
T
T
Mitsui
Y
Y
Aozasa
N
N
Kubo
T
T
Natori
S
S
D000595:Amino Acid Sequence; D000818:Animals; D017089:Ankyrin Repeat / Q000235:genetics; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D004330:Drosophila / Q000235:genetics; D020573:Genes, rel / Q000235:genetics*; D007150:Immunohistochemistry; D007313:Insecta; D019913:Nuclear Localization Signals / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics; D017434:Protein Structure, Tertiary; D020569:Proto-Oncogene Proteins c-rel / Q000737:chemistry* / Q000235:genetics / Q000648:ultrastructure*; D017386:Sequence Homology, Amino Acid
D018076:DNA, Complementary; D019913:Nuclear Localization Signals; D020569:Proto-Oncogene Proteins c-rel