title: Amino-terminal extension of 146 residues of L-type GATA-6 is required for transcriptional activation but not for self-association.
abstract: Transcription factor GATA-6 plays essential roles in developmental processes and tissue specific functions through regulation of gene expression. GATA-6 mRNA utilizes two Met-codons in frame as translational initiation codons. Deletion of the nucleotide sequence encoding the PEST sequence (Glu(31)-Cys(46)) between the two initiation codons unusually reduced the protein molecular size on SDS-polyacrylamide gel-electrophoresis, and re-introduction of this sequence reversed this change. The long-type (L-type) GATA-6 containing this PEST sequence self-associated similarly to the short-type (S-type) GATA-6, as determined on co-immunoprecipitation of Myc-tagged GATA-6 with HA-tagged GATA-6. The L-type and S-type GATA-6 also interacted mutually. The L-type GATA-6 without the PEST sequence also self-associated and interacted with the S-type GATA-6. The transcriptional activation potential of L-type GATA-6 is higher than that of S-type GATA-6. When the PEST sequence (Glu(31)-Cys(46)) was inserted into the L-type GATA-6 without Arg(13)-Gly(101), the resultant recombinant protein showed significantly higher transcriptional activity, while the construct with an unrelated sequence exhibited lower activity. These results suggest that the Glu(31)-Cys(46) segment plays an important role in the transcriptional activation, although it does not participate in the self-association.
authors.affiliation: Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: Kayoko
authors.initials: K
authors.lastname: Takada
authors.affiliation: Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: Kanako
authors.initials: K
authors.lastname: Obayashi
authors.affiliation: Department of Medical Biochemistry, School of Pharmacy, Iwate Medical University, Nishitokuta 2-1-1, Shiwa, Iwate 028-3694, Japan.
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Ohashi
authors.affiliation: Department of Immunobiology, School of Pharmacy, Iwate Medical University, Nishitokuta 2-1-1, Shiwa, Iwate 028-3694, Japan.
authors.forename: Ayako
authors.initials: A
authors.lastname: Ohashi-Kobayashi
authors.affiliation: Department of Biochemistry, School of Pharmacy, Iwate Medical University, Nishitokuta 2-1-1, Shiwa, Iwate 028-3694, Japan.
authors.forename: Mayumi
authors.initials: M
authors.lastname: Nakanishi-Matsui
authors.affiliation: Department of Molecular Biology, School of Pharmacy, Iwate Medical University, Nishitokuta 2-1-1, Shiwa, Iwate 028-3694, Japan. Electronic address: mmaeda@iwate-med.ac.jp.
authors.forename: Masatomo
authors.initials: M
authors.lastname: Maeda
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D019556:COS Cells; D002522:Chlorocebus aethiops; D050993:GATA6 Transcription Factor / Q000737:chemistry / Q000235:genetics*; D008969:Molecular Sequence Data; D013329:Structure-Activity Relationship; D014158:Transcription, Genetic / Q000235:genetics*; D015533:Transcriptional Activation / Q000235:genetics*
chemical_list: D050993:GATA6 Transcription Factor
keywords: GATA-6; Leaky ribosomal scanning; PEST sequence; Self-association; Transcription factor