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PubMed · 10821432

Cell type-dependent transactivation or repression of mesoderm-restricted basic helix-loop-helix protein, POD-1/Capsulin.

M Miyagishi·M Hatta·T Ohshima·J Ishida·R Fujii·T Nakajima·A Fukamizu
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Abstract

A family of basic-helix-loop-helix (bHLH) nuclear factors play important roles in controlling cell growth and differentiation as critical regulatory components in transcription. Here we describe molecular characterization of mesoderm-specific bHLH protein, POD-1/Capsulin. Transactivation property of POD-1/Capsulin was analyzed by the Gal4 fusion system in six mammalian cell lines. The results indicated that an activation property was shown in HT1080 and HeLa cells, but a repression activity in HepG2 cells. Mapping analysis for the transactivation and repression activities revealed that the C-terminal domain of POD-1/Capsulin is essential for the transactivation and both the N-terminal and C-terminal domains are contributed to the repression activities. Furthermore, in order to identify possible interactants of the POD-1/Capsulin, we performed yeast two-hybrid screen in a human kidney cDNA library, and identified a class A bHLH protein, ITF-2 as potential heterodimeric partner of the bHLH protein.

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3T3 CellsAnimalsBasic Helix-Loop-Helix ProteinsBlotting, WesternCOS CellsCell LineGlutathione TransferaseHeLa CellsHelix-Loop-Helix MotifsHumansMesodermMicePrecipitin TestsProtein Structure, TertiaryTranscription FactorsTranscription, GeneticTranscriptional ActivationTumor Cells, CulturedTwo-Hybrid System Techniquesbeta-GalactosidaseJournal ArticleResearch Support, Non-U.S. Gov't

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M Miyagishi, M Hatta, T Ohshima, J Ishida, R Fujii, T Nakajima, A Fukamizu. 2000. Cell type-dependent transactivation or repression of mesoderm-restricted basic helix-loop-helix protein, POD-1/Capsulin.. https://doi.org/10.1023/a%3A1007057611868

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