Related Experiment Video
Updated: Oct 1, 2026

Identification of Cyclin-dependent Kinase 1 Specific Phosphorylation Sites by an In Vitro Kinase Assay
Published on: May 3, 2018
Different proteins are phosphorylated under acidic environments in Jurkat cells
Toshihiko Fukamachi1, Hiromi Saito, Tomohito Kakegawa
1Graduate School of Pharmaceutical Sciences, Chiba University, 1-33, Yayoi-cho, Inage-ku, Chiba, Japan.
Abstract:
In order to test the ability of immune cells to grow under acidic conditions, Jurkat cells were cultured in medium at pH 6.3. At this acidic pH, the cells required approximately 2 days per generation, while the generation time was approximately 1 day for cells grown in near neutral medium. Western blot analysis using anti-phosphotyrosine antibody (4G10) showed that protein phosphorylation was affected by external pH. For example, the level of a 66-kDa phosphoprotein increased dramatically in acidic medium, whereas the amount of a 34-kDa phosphoprotein decreased. These results suggest that Jurkat cells use different signal pathways under acidic environments.
Related Concept Videos
Protein Kinases and Phosphatases
Protein kinases
Many proteins in the cell are regulated by phosphorylation, the addition of a phosphate group. A family of enzymes called kinases...
Phosphorylation
During phosphorylation, protein kinases transfer the terminal phosphate group of ATP to specific amino acid side chains of substrate proteins. Serine, threonine, and tyrosine are the most commonly...
Covalently Linked Protein Regulators
These groups modify specific amino acids in a protein.
The JAK-STAT Signaling Pathway
Regulated Protein Degradation
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
Anaphase Promoting Complex
