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ACTH Modulates PTP-PEST Activity and Promotes Its Interaction With Paxillin
Alejandra Beatriz Gorostizaga1, M Mercedes Mori Sequeiros Garcia1, Andrea B Acquier1,2
1Department of Biochemistry, School of Medicine, Institute for Biomedical Research (INBIOMED), University of Buenos Aires-CONICET, Buenos Aires, Argentina.
Journal of Cellular Biochemistry
|April 11, 2016
Summary
Adrenocorticotropic hormone (ACTH) activates protein tyrosine phosphatase-PEST (PTP-PEST) in adrenal cells, increasing its interaction with paxillin. This study identifies PTP-PEST as a key regulator in ACTH signaling pathways.
Area of Science:
- Endocrinology
- Cell Biology
- Biochemistry
Background:
- Adrenocorticotropic hormone (ACTH) influences adrenal function by modulating protein dephosphorylation.
- Previous studies indicated ACTH activates a 115-kDa protein tyrosine phosphatase (PTP115) in rat adrenal zona fasciculata (ZF).
Purpose of the Study:
- To identify PTP115 and elucidate its role in ACTH-mediated signaling.
- To investigate the regulation and substrate interaction of PTP-PEST in the adrenal gland.
Main Methods:
- Partial purification of PTP115 from rat adrenal ZF.
- Western blot analysis to detect PTP-PEST.
- Immunohistochemistry and RT-PCR for PTP-PEST expression.
- siRNA to reduce PTP-PEST expression.
- Enzyme kinetics and co-immunoprecipitation assays.
Main Results:
- PTP115 was identified as PTP-PEST, which dephosphorylates paxillin.
- PTP-PEST is expressed in rat adrenal ZF and Y1 adrenocortical cells.
- ACTH/PKA signaling regulates PTP-PEST activity and enhances its interaction with paxillin.
Conclusions:
- PTP-PEST is expressed and regulated by ACTH/PKA in the adrenal gland.
- ACTH stimulation promotes PTP-PEST interaction with paxillin, suggesting a role in adrenal cell signaling.
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