Na^+和Ca^(2+)对拟南芥根原生质体质膜内向K^+通道电流的影响

Effects of Na^+ and Ca^(2+) on the inward K^+ current in the plasma membrane of Arabidopsis root cells

以拟南芥 ArabidopsisthalianaColumbia 根为材料,利用膜片钳技术测定其根细胞原生质体质膜内向K+电流,并对Na+对其K+电流的影响进行了初步研究,发现Na+可明显抑制拟南芥根细胞原生质体的内向K+电流,外施Ca2+可缓解Na+对内向K+电流的抑制.说明Ca2+参与了质膜上K+通道对K+/Na+的选择性吸收的调节,从而使植物适应盐胁迫.

Using patch-clamp techniques,we examined the K^+ channel activity in the plasma membrane of root cells from Arabidopsis thaliana (ecotype Columbia) after NaCl treatment.Inward currents in the root cells were significantly decreased within 5 min after 50 mmol/L NaCl was perfused to the bath solution.However,addition of 5 mmol/L Ca^(2+) recovered the decrease of inward-rectifying current.These suggest that Ca^(2+) is involved in the regulation of selective uptake of Na^+/K^+ through K^+ channel in root cells under higher Na^+ concentration,leading to adaptation of plants to salt stress.