Inositol phosphate multikinase dependent transcriptional control.
Ace J Hatch1, Audrey R Odom1, John D York2
1Departments of Pharmacology and Cancer Biology and of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA.
Advances in Biological Regulation
|March 27, 2017
Summary
Inositol phosphate production by inositol polyphosphate multikinase (IPMK) is vital for cellular adaptation. Restoring IPMK’s enzymatic activity and Mcm1 protein levels re-establishes gene expression in cells lacking IPMK.
Area of Science:
- Molecular Biology
- Cellular Biology
- Biochemistry
Background:
- Inositol phosphates (IPs) are crucial for cellular adaptive responses.
- Inositol polyphosphate multikinase (IPMK), also known as Ipk2 or Arg82, regulates IP production.
- IPMK links gene expression control with IP metabolism through kinase-dependent and independent functions.
Purpose of the Study:
- To identify the cis-element mediating IPMK functions.
- To investigate the mechanism of IPMK's dual role in gene expression.
- To restore gene expression in cells lacking IPMK.
Main Methods:
- Defined a specific promoter sequence (5'-CCCTAAAAGG-3') interacting with IPMK.
- Employed a synthetic biology approach for add-back experiments.
- Assessed restoration of gene expression by restoring IP4/IP5 production and Mcm1 protein levels.
Main Results:
- Identified a cis-element mediating both kinase-dependent and independent IPMK functions.
- Demonstrated that restoring IP4/IP5 production and Mcm1 levels rescues gene expression in IPMK-deficient cells.
- Provided evidence for IPMK's dual role in stabilizing transcription factors and producing a small molecule code.
Conclusions:
- IPMK possesses dual functionality essential for coordinating biological processes.
- IPMK stabilizes transcription factor levels and generates a molecular code for gene expression control.
- The identified cis-element is key to IPMK's regulatory role in cellular adaptation.
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