Genomic organization, chromosomal localization, and promoter of human gene for FK506-binding protein 12.6.
Cyclic ADP-ribose (cADPR) induces the release of Ca2+ from microsomes of pancreatic islets for insulin secretion. It has been demonstrated that cADPR binds to FK506-binding protein 12.6 (FKBP 12.6) on rat islet ryanodine receptor and that the binding of cADPR to FKBP12.6 frees the ryanodine receptor from FKBP12.6, causing it to release Ca2+ [Noguchi, N., Takasawa, S., Nata, K., Tohgo, A., Kato, I., Ikehata, F., Yonekura, H., Okamoto, H., 1997. Cyclic ADP-ribose binds to FK506-binding protein to release Ca2+ from islet microsomes. J. Biol. Chem. 272, 3133-3136.]. In this study, we cloned, characterized the structural organization of the human FKBP12.6, which is highly homologous to human FKBP12, and analyzed the promoters for FKBP12.6 and FKBP12. Human FKBP12.6 gene spanned about 16 kb in length and consisted of four exons and three introns. The positions of exon-intron junction of the FKBP12.6 gene were perfectly matched with those of FKBP12 gene except that FKBP12 has an additional exon, exon V, to code exclusively for 3'-UTR. Fluorescence in situ hybridization revealed that the FKBP12.6 gene was located on chromosome 2 p21-23, which is different from the locus (chromosome 20 p13) of the FKBP12 gene. Reporter gene analyses revealed that the regions of -58 approximately -24 of FKBP12.6 and -106 approximately -79 of FKBP12 are important for promoter activities. The promoters contain a consensus transcription factor binding sequence for Sp family in FKBP12.6 and Ets-1 in FKBP12. Electrophoretic mobility shift assays showed that nuclear proteins bind to the promoters. The DNA/protein complex on FKBP12.6 promoter was competed out by Sp1 consensus probe and the complex was supershifted by anti-Sp3 antibodies. On the other hand, the DNA/protein complex on FKBP12 promoter was competed out by Ets-1 consensus probe but not by its mutant probe, indicating that Sp3 and Ets-1 play an essential role in transcription of FKBP12.6 and FKBP12, respectively.
Nakazawa
Tetsuya
T
Department of Biochemistry, Tohoku University Graduate School of Medicine, Sendai 980-8575, Miyagi, Japan.
Takasawa
Shin
S
Noguchi
Naoya
N
Nata
Koji
K
Tohgo
Akira
A
Mori
Mitsuko
M
Nakagawara
Kan-ichi
K
Akiyama
Takako
T
Ikeda
Takayuki
T
Yamauchi
Akiyo
A
Takahashi
Iwao
I
Yoshikawa
Takeo
T
Okamoto
Hiroshi
H
D020413:3' Untranslated Regions; D001483:Base Sequence; D002478:Cells, Cultured; D002889:Chromosomes, Human, Pair 2 / Q000235:genetics*; D024202:Electrophoretic Mobility Shift Assay; D005091:Exons / Q000235:genetics*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007438:Introns / Q000235:genetics*; D007668:Kidney / Q000378:metabolism; D008156:Luciferases / Q000378:metabolism; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000235:genetics*; D050784:Proto-Oncogene Protein c-ets-1 / Q000378:metabolism; D016329:Sp1 Transcription Factor / Q000378:metabolism; D051705:Sp3 Transcription Factor / Q000378:metabolism; D022061:Tacrolimus Binding Protein 1A / Q000235:genetics*; D022021:Tacrolimus Binding Proteins / Q000235:genetics*
D020413:3' Untranslated Regions; D050784:Proto-Oncogene Protein c-ets-1; C497121:SP3 protein, human; D016329:Sp1 Transcription Factor; D051705:Sp3 Transcription Factor; D008156:Luciferases; D022061:Tacrolimus Binding Protein 1A; D022021:Tacrolimus Binding Proteins; C403484:tacrolimus binding protein 1B