盐味感知
中文名称
通路描述
最初，I 类味蕾细胞被认为负责感知低浓度的盐味，但现已认为 II 类味蕾细胞中的某些亚群负责此功能（Nomura 等，2020）。盐味感知细胞的身份仍是当前研究的课题。感知低浓度盐的能力至少部分归因于一种对氨甲酰化胺敏感的钠通道，该通道被认为是 SCNN 通道（ENaC 通道）。SCNN 复合物包含孔形成亚基 SCNN1A 或 SCNN1D，以及调节亚基 SCNN1B 和 SCNN1G，这些亚基均在人类味蕾中被检测到（Rossier 等，2004，Stähler 等，2008）。SCNN1A 在 mice 中的敲除消除了对氨甲酰化胺敏感的盐味及对低浓度盐的吸引力，然而 SCNN1B 和 SCNN1G 在 mice 的味蕾细胞中不与 SCNN1A 共定位（Lossow 等，2020），这引发了关于 SCNN 复合物亚基组成的疑问。SCNN1D 存在于人类味蕾细胞中，但存在于小鼠味蕾细胞中。
在人类中，位于细胞膜上的含有 SCNN1A 或 SCNN1D 的 SCNN 通道被认为将钠离子从细胞外区域转运到细胞质中，导致去极化，从而引起 CALHM1:CALHM3 通道开放，释放 ATP 作为神经递质从细胞质到细胞外区域。
在人类中，位于细胞膜上的含有 SCNN1A 或 SCNN1D 的 SCNN 通道被认为将钠离子从细胞外区域转运到细胞质中，导致去极化，从而引起 CALHM1:CALHM3 通道开放，释放 ATP 作为神经递质从细胞质到细胞外区域。
英文描述
Sensory perception of salty taste Initially, type I taste bud cells were suggested to be responsible for tasting low concentrations of salt, however a subset of type II taste bud cells are now thought to be responsible (Nomura et al. 2020). The identity of salt-tasting cells remains a subject of current research. The ability to taste low concentrations of salt is at least partially due to an amiloride-sensitive sodium channel believed to be an SCNN channel (ENaC channel). SCNN complexes contain the pore-forming subunit SCNN1A or SCNN1D, and the modulatory subunits SCNN1B and SCNN1G, all of which have been detected in human taste buds (Rossier et al. 2004, Stähler et al. 2008). Knockout of SCNN1A in mice abolished amiloride-sensitive salt taste and attraction to low concentrations of salt, however SCNN1B and SCNN1G do not colocalize with SCNN1A in taste cells of mice (Lossow et al. 2020), raising the question of the subunit composition of the SCNN complex. SCNN1D is present in human taste cells but not in mouse taste cells.
In humans, a SCNN channel containing SCNN1A or SCNN1D located in the plasma membrane is believed to transport sodium ions from the extracellular region into the cytosol, resulting in depolarization that causes CALHM1:CALHM3 channels to open and release ATP, a neurotransmitter, from the cytosol to the extracellular region.
In humans, a SCNN channel containing SCNN1A or SCNN1D located in the plasma membrane is believed to transport sodium ions from the extracellular region into the cytosol, resulting in depolarization that causes CALHM1:CALHM3 channels to open and release ATP, a neurotransmitter, from the cytosol to the extracellular region.
所含基因
6 个基因