Cyclic AMP-dependent proteolysis of GATA-6 expressed on the intracellular membrane.
Cyclic AMP-dependent proteolysis of GATA-6 was characterized by fusing GATA-6 with the carboxyl-terminal membrane domain of SREBP-2. When the fusion protein was stably expressed in CHO-K1 cells, it was recovered in the ER membrane. This protein was processed in a similar manner to SREBP-2 upon cholesterol starvation, and the GATA-6 moiety moved into the nucleus. The GATA-6 moiety on the membrane became undetectable in the presence of dbcAMP or cholera toxin. However, H-89, K-252a, MG115 and lactacystin inhibited this decrease, suggesting that the cytoplasmic GATA-6 moiety of the fusion protein was degraded by proteasomes though A-kinase upon elevation of the cellular cAMP concentration.
Tsuge
Takeshi
T
Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka 565-0871, Japan.
Uetani
Kae
K
Sato
Ryuichiro
R
Ohashi-Kobayashi
Ayako
A
Maeda
Masatomo
M
D000818:Animals; D003994:Bucladesine / Q000378:metabolism; D016466:CHO Cells; D002784:Cholesterol / Q000378:metabolism; D006224:Cricetinae; D003412:Cricetulus; D000242:Cyclic AMP / Q000378:metabolism*; D004721:Endoplasmic Reticulum / Q000378:metabolism / Q000648:ultrastructure; D004791:Enzyme Inhibitors / Q000378:metabolism; D050993:GATA6 Transcription Factor / Q000378:metabolism*; D006801:Humans; D007425:Intracellular Membranes / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism*; D051782:Sterol Regulatory Element Binding Protein 2 / Q000235:genetics / Q000378:metabolism
D004791:Enzyme Inhibitors; D050993:GATA6 Transcription Factor; D011993:Recombinant Fusion Proteins; D051782:Sterol Regulatory Element Binding Protein 2; D003994:Bucladesine; D002784:Cholesterol; D000242:Cyclic AMP