Dossena Silvia, Nofziger Charity, Lang Florian, Valenti Giovanna, Paulmichl Markus
Institute of Pharmacology and Toxicology, Paracelsus Medical University, Salzburg, Austria.
Cell Physiol Biochem. 2011;28(3):377-84. doi: 10.1159/000335101. Epub 2011 Nov 16.
Human pendrin (SCL26A4, PDS) is a 780 amino acid integral membrane protein with transport function. It acts as an electroneutral, sodium-independent anion exchanger for a wide range of anions, such as iodide, chloride, formate, bicarbonate, hydroxide and thiocyanate. Pendrin expression was originally described in the thyroid gland, kidney and inner ear. Accordingly, pendrin mutations with reduction or loss of transport function result in thyroid and inner ear abnormalities, manifested as syndromic (Pendred syndrome) and non-syndromic hearing loss with an enlarged vestibular aqueduct (ns-EVA). Pendred syndrome, the most common form of syndromic deafness, is an autosomal recessive disease characterized by sensorineural deafness due to inner ear malformations and a partial iodide organification defect that may lead to thyroid goiter. Later, it became evident that not only pendrin loss of function, but also up-regulation could participate in the pathogenesis of human diseases. Indeed, despite the absence of kidney dysfunction in Pendred syndrome patients, evidence exists that pendrin also plays a crucial role in this organ, with a potential involvement in the pathogenesis of hypertension. In addition, recent data underscore the role of pendrin in exacerbations of respiratory distresses including bronchial asthma and chronic obstructive pulmonary disease (COPD). Pendrin expression in other organs such as mammary gland, testis, placenta, endometrium and liver point to new, underscored pendrin functions that deserve to be further investigated.
人pendrin（SCL26A4，PDS）是一种具有780个氨基酸的整合膜蛋白，具有转运功能。它作为一种电中性、不依赖钠的阴离子交换体，可转运多种阴离子，如碘离子、氯离子、甲酸根离子、碳酸氢根离子、氢氧根离子和硫氰酸根离子。Pendrin最初在甲状腺、肾脏和内耳中被发现。因此，具有转运功能降低或丧失的pendrin突变会导致甲状腺和内耳异常，表现为综合征性（ Pendred综合征）和伴有前庭导水管扩大的非综合征性听力损失（ns-EVA）。Pendred综合征是综合征性耳聋最常见的形式，是一种常染色体隐性疾病，其特征是由于内耳畸形导致的感音神经性耳聋以及可能导致甲状腺肿大的部分碘有机化缺陷。后来发现，不仅pendrin功能丧失，而且其上调也可能参与人类疾病的发病机制。事实上，尽管Pendred综合征患者没有肾功能障碍，但有证据表明pendrin在该器官中也起着关键作用，可能参与高血压的发病机制。此外，最近的数据强调了pendrin在包括支气管哮喘和慢性阻塞性肺疾病（COPD）在内的呼吸窘迫加重中的作用。Pendrin在乳腺、睾丸、胎盘、子宫内膜和肝脏等其他器官中的表达表明其具有新的、值得进一步研究的重要功能。
