Table 4.

Overview of proteins participating in the regulation of kinases or phosphatases known to interact with tau protein and their roles in pathology.

Protein	Roles in Tau Pathology	References
PTPA	regulatory subunit of PPP2C (A, B); decreased expression in AD; enhances tau dephosphorylation; neuroprotective; regulate autophagic degradation of proteins	[223,224,229,230]
CDC37	regulates tau phosphorylation, enhances phospho-tau stability at HSP90 scaffold, preventing its degradation, preserves CDK5 and AKT kinases	[231]
PIK3R1	key unit of PI3K, part of the PI3K/AKT1/GSK3B signaling pathway, which is downregulated in AD, plays a role in insulin signaling pathway where it might exacerbate AD pathology	[232,233,234,235]
S100B	inhibits tau phosphorylation; enhances tau dephosphorylation by PPP5C; overexpression of S100B causes apoptosis, tau hyperphosphorylation, and inflammation	[236,237,238,239,240]