TPST2 Human

Tyrosylprotein Sulfotransferase 2 (TPST2) is an enzyme that catalyzes the O-sulfation of tyrosine residues within acidic regions of proteins. This post-translational modification is crucial for various biological processes, including protein-protein interactions, cell signaling, and immune responses . TPST2 is a type II integral membrane protein predominantly found in the Golgi apparatus .

Recombinant human TPST2 is typically produced using Chinese Hamster Ovary (CHO) cells. The protein is expressed with a C-terminal 6-His tag to facilitate purification . The preparation involves several steps:

1. Gene Cloning: The TPST2 gene is cloned into an expression vector suitable for CHO cells.
2. Transfection: The vector is introduced into CHO cells, which are then cultured under conditions that promote protein expression.
3. Purification: The expressed protein is purified using affinity chromatography, exploiting the 6-His tag for binding to a nickel column .
4. Validation: The purity and activity of the recombinant protein are validated using SDS-PAGE and enzyme activity assays .

TPST2 catalyzes the transfer of sulfate from 3’-phosphoadenylyl sulfate (PAPS) to tyrosine residues in target proteins. This reaction is essential for the function of various proteins involved in hemostasis, metabolism, and immune responses . The enzyme’s activity can be measured by its ability to sulfate specific peptide substrates, such as PSGL-1 .

Recent studies have highlighted the role of TPST2 in modulating immune responses. For instance, TPST2 has been shown to suppress interferon-γ signaling by sulfating the interferon-γ receptor 1, thereby influencing cancer immunity . Additionally, chemical synthesis of sulfated proteins has revealed that tyrosine sulfation enhances the inhibitory potency of thrombin-inhibiting proteins, underscoring the importance of this modification in anticoagulant activity .