The Evolutionary Aspects of Aquaporin Family.
The Evolutionary Aspects of Aquaporin Family.
复制标题
DOI：
10.1007/978-94-024-1057-0_2
复制
发表时间：
2017-01-01
影响因子：
--
通讯作者：
Tanaka, Yasuko
中科院分区：
文献类型：
--
作者：
Ishibashi, Kenichi;Morishita, Yoshiyuki;Tanaka, Yasuko
水通道蛋白（Aquaporins，AQP）是一个跨膜蛋白家族，广泛存在于包括病毒在内的所有生物体内。基于高度保守的成孔NPA基序周围的序列，它们大致分为三个亚家族：（1）经典的水选择性AQP（CAQP），（2）甘油可渗透的水甘油孔蛋白（AQGP）和（3）AQP超基因通道，超水孔蛋白（SAQP）。AQP由两个保守的三个跨膜结构域的串联重复序列和一个NPA基序组成。AQP的祖先可能起源于原核生物，通过复制半个AQP基因，通过进化一个亚家族特异性羧基末端NPA基序，分化为CAQP或AQGP。这两个AQP亚家族可能已被带到单细胞真核生物的祖先，原生生物，并进一步到多细胞生物。虽然真菌谱系保留了两个AQP亚家族，但植物谱系在藻类祖先之后已经失去了AQGP，CAQP广泛多样化为PIP，TIP，SIP，XIP，HIP和LIP，NIP可能从细菌水平转移。有趣的是，动物谱系已经获得了新的SAQP亚家族，具有高度偏离的NPA基序，特别是在前口动物和后口动物的氨基末端的一半。在哺乳动物中，前口类谱系在Hypltera之后已经失去了AQGP，而后口类谱系保留了所有三个亚科，直到脊椎动物，具有多样化的CAQP（AQP0，1，2，4，5，6，8）和AQGP（AQP3，7，9，10），具有有限的SAQP（AQP11，12）。全基因组复制、局部基因复制和水平基因转移可能导致了AQP的多样性，并伴随着适应性选择和功能改变以响应环境变化。从进化的角度出发，可以通过物种间的比较来推测各个AQP的功能，从而对AQP的生理作用有新的认识。AQP研究中的这种进化指导将导致对水和溶质稳态的更深入理解。
Aquaporins (AQPs ) are a family of transmembrane proteins present in almost all species including virus. They are grossly divided into three subfamilies based on the sequence around a highly conserved pore-forming NPA motif: (1) classical water -selective AQP (CAQP), (2) glycerol -permeable aquaglyceroporin (AQGP) and (3) AQP super-gene channel, superaquaporin (SAQP). AQP is composed of two tandem repeats of conserved three transmembrane domains and a NPA motif. AQP ancestors probably started in prokaryotes by the duplication of half AQP genes to be diversified into CAQPs or AQGPs by evolving a subfamily-specific carboxyl-terminal NPA motif. Both AQP subfamilies may have been carried over to unicellular eukaryotic ancestors, protists and further to multicellular organisms. Although fungus lineage has kept both AQP subfamilies, the plant lineage has lost AQGP after algal ancestors with extensive diversifications of CAQPs into PIP, TIP, SIP, XIP, HIP and LIP with a possible horizontal transfer of NIP from bacteria. Interestingly, the animal lineage has obtained new SAQP subfamily with highly deviated NPA motifs, especially at the amino-terminal halves in both prostomial and deuterostomial animals. The prostomial lineage has lost AQGP after hymenoptera, while the deuterostomial lineage has kept all three subfamilies up to the vertebrate with diversified CAQPs (AQP0, 1, 2, 4, 5, 6, 8) and AQGPs (AQP3, 7, 9, 10) with limited SAQPs (AQP11, 12) in mammals. Whole-genome duplications, local gene duplications and horizontal gene transfers may have produced the AQP diversity with adaptive selections and functional alternations in response to environment changes. With the above evolutionary perspective in mind, the function of each AQP could be speculated by comparison among species to get new insights into physiological roles of AQPs . This evolutionary guidance in AQP research will lead to deeper understandings of water and solute homeostasis.