Objective To explore the feasibility of adding a flexible linker between two-pore-domain potassium channel TREK-1 (TWIK related K + channel 1)monomers to construct a tandem-linked dimer.Methods PCR was used to add a flexible linker between the two TREK-1 monomers.The cRNA obtained from in vitro transcription using the above vector was injected into Xenopus oocytes.After 24 -48 h,currents were recorded from these oocytes using a two-electrode voltage clamp.The effects of extracellular Ba2 + and pH on TdTREK-1 were observed and compared with those of native dimeric TREK-1.Results The tandem-linked dimeric TdTREK-1 was highly expressed in Xenopus oocytes.The currents through these channels were inhibited by extracellular Ba2 +and acidification.Furthermore,the responsiveness of the concatenated dimers to these extracellular stimuli was similar to that of native dimers.Conclusion Adding a flexible linker between the two monomers to construct the tandem-linked dimer does not affect the expression and gating properties of TREK-1, suggesting that the method be feasible.Such a method will allow the manipulation of a single subunit,which will help basis study the structure and function of TREK-1.