Abstract
Attachment of lipid tails to oligonucleotides has emerged as a powerful technology in constructing cell membrane-anchorable nucleic acid-based probes. In practice, however, conventional lipid-conjugated oligonucleotides fail to distinguish among different cell membranes. Herein, a phosphorylated lipid-conjugated oligonucleotide (DNA-lipid-P) is reported for alkaline phosphatase (ALP)-dependent cell membrane adhesion. In the absence of ALP, DNA-lipid-P with its poor hydrophobicity shows only weak interaction with cell membrane. However, in the presence of the highly expressed plasma membrane-associated ALP, DNA-lipid-P is converted to lipid-conjugated oligonucleotide (DNA-lipid) by enzymatic dephosphorylation. As a result of such conversion, the generated DNA-lipid has greater hydrophobicity than DNA-lipid-P and is thus able to insert into cell membranes in situ. Accordingly, DNA-lipid-P enables selective anchoring on cell membranes with elevated ALP level. Since elevated ALP level is a critical index of some diseases and even cancers, DNA-lipid-P holds promise for cell membrane engineering and disease diagnostics at the molecular level.