title: Systematic method to obtain novel genes that are regulated by mi transcription factor: impaired expression of granzyme B and tryptophan hydroxylase in mi/mi cultured mast cells.
abstract: The mi locus encodes a member of the basic-helix-loop-helix-leucine zipper protein family of transcription factors (hereafter called MITF). We have reported that the expression of several genes was impaired in cultured mast cells (CMCs) of mi/mi genotype, and demonstrated the involvement of MITF in the transcription of these genes. To obtain new genes whose transcription may be regulated by MITF, we prepared a subtracted cDNA library using +/+ and mi/mi CMCs. We found two clones carrying the granzyme (Gr) B and tryptophan hydroxylase (TPH) cDNAs in the subtracted library. The expression of the Gr B and TPH genes decreased in mi/mi CMCs, and recovered to nearly normal level by the overexpression of normal (+) MITF but not of mutant (mi) MITF. The +-MITF bound three and one CANNTG motifs in the Gr B and TPH promoters, respectively, and transactivated these two genes, indicating the involvement of +-MITF in their expression. Because TPH is the rate-limiting enzyme for serotonin synthesis, we examined the serotonin content of +/+ and mi/mi CMCs. The serotonin content was significantly smaller in mi/mi CMCs than in +/+ CMCs. The introduction of +-MITF but not of mi-MITF normalized the serotonin content in mi/mi CMCs.
authors.affiliation: Department of Pathology, Medical School, Osaka University, Suita, Osaka 565, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Ito
authors.forename: E
authors.initials: E
authors.lastname: Morii
authors.forename: K
authors.initials: K
authors.lastname: Maeyama
authors.forename: T
authors.initials: T
authors.lastname: Jippo
authors.forename: D K
authors.initials: DK
authors.lastname: Kim
authors.forename: Y M
authors.initials: YM
authors.lastname: Lee
authors.forename: H
authors.initials: H
authors.lastname: Ogihara
authors.forename: K
authors.initials: K
authors.lastname: Hashimoto
authors.forename: Y
authors.initials: Y
authors.lastname: Kitamura
authors.forename: H
authors.initials: H
authors.lastname: Nojima
mesh_terms: D000818:Animals; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins / Q000235:genetics*; D005786:Gene Expression Regulation; D015723:Gene Library; D053804:Granzymes; D006640:Histidine Decarboxylase / Q000235:genetics; D008407:Mast Cells / Q000502:physiology; D051379:Mice; D008817:Mice, Mutant Strains; D051739:Microphthalmia-Associated Transcription Factor; D012697:Serine Endopeptidases / Q000235:genetics; D012701:Serotonin / Q000502:physiology; D014157:Transcription Factors / Q000235:genetics*; D053802:Tryptases; D014365:Tryptophan Hydroxylase / Q000235:genetics
chemical_list: D004268:DNA-Binding Proteins; D051739:Microphthalmia-Associated Transcription Factor; C497235:Mitf protein, mouse; C509190:Tpsb2 protein, mouse; D014157:Transcription Factors; D012701:Serotonin; D014365:Tryptophan Hydroxylase; D053804:Granzymes; C509214:Gzmb protein, mouse; D012697:Serine Endopeptidases; C509222:Tpsab1 protein, mouse; D053802:Tryptases; D006640:Histidine Decarboxylase