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Published on: August 13, 2017
The Pyst2-L phosphatase is involved in cell-crowding
Orlev Levy-Nissenbaum1, Shlomit Ben-Menachem, Orit Sagi-Assif
1Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel-Aviv University, 69978 Tel Aviv, Israel. orle@post.tau.ac.il
Immunology Letters
|January 3, 2006
Summary
The dual-specificity phosphatase Pyst2-L is overexpressed in certain cancers and plays a role in cell cycle regulation. Its expression is reduced in G2-phase cells, suggesting a role in cell cycle control and cellular crowding responses.
Area of Science:
- Molecular Biology
- Cell Biology
- Genomics
Background:
- The dual-specificity phosphatase Pyst2-L is overexpressed in acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), solid tumors, and lymphoblastoid cell lines.
- Pyst2-L dephosphorylates pERK and pJNK proteins, regulating the MAP kinase signaling pathway.
Purpose of the Study:
- To identify genes homologous to Pyst2-L using comparative genomics.
- To investigate the role of Pyst2-L in cell cycle regulation and cellular crowding.
Main Methods:
- Comparative genomic analysis of multi-organism databases to find Pyst2-L homologs.
- Sequence analysis to identify homologous genes.
- Cell synchronization techniques (alpha-factor) and expression level analysis in human K562 cells and yeast (Saccharomyces cerevisiae).
Main Results:
- Xenopus laevis MAP kinase phosphatase X17c and Yeast Yvh1p genes show high homology to Pyst2-L.
- Yvh1p gene expression is downregulated in G2-phase synchronized yeast.
- Pyst2-L expression is reduced in G2-phase synchronized human K562 cells.
- High levels of Pyst2-L phosphatase are expressed in crowded cell cultures.
Conclusions:
- Homologous genes X17c and Yvh1p are involved in cell cycle regulation.
- Low Pyst2-L phosphatase levels may be essential for the G2-phase of the cell cycle.
- Pyst2-L might participate in signaling pathways triggered by cellular crowding.
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