Phospho-PKC未 (Thr505) refers to the phosphorylation of protein kinase C delta (PKC未) at threonine residue 505, a modification that is crucial for its activation and function. PKC未 is a member of the protein kinase C (PKC) family, which are serine/threonine kinases involved in various cellular signaling pathways, including regulation of cell growth, apoptosis, and differentiation. The phosphorylation at Thr505 is particularly important for the kinase activity of PKC未 and its role in the G1 to S phase transition during cell cycle progression. This phosphorylation site is specific to PKC未, and antibodies targeting Phospho-PKC未 (Thr505) do not cross-react with other PKC isoforms, making it a valuable marker for studying PKC未's unique functions.