Intact and N- or C-terminal end truncated AQP0 function as open water channels and cell-to-cell adhesion proteins: end truncation could be a prelude for adjusting the refractive index of the lens to prevent spherical aberration.
Intact and N- or C-terminal end truncated AQP0 function as open water channels and cell-to-cell adhesion proteins: end truncation could be a prelude for adjusting the refractive index of the lens to prevent spherical aberration.
复制标题
DOI：
10.1016/j.bbagen.2014.05.002
复制
发表时间：
2014-09
影响因子：
3
通讯作者：
Varadaraj, Kulandaiappan
中科院分区：
文献类型：
--
作者：
Kumari, S. Sindhu;Varadaraj, Kulandaiappan
关键词：
研究晶状体成熟纤维细胞水通道蛋白0 （AQP0）的N端或c端翻译后截断对水渗透性（Pw）和细胞间粘附（CTCA）功能的影响。以下缺失/截断是通过定点诱变产生的（名称在括号中）：氨基酸残基（AA） 2-6 （AQP0-N-del-2-6）、AA235-263 （AQP0-1-234）、AA239-263 （AQP0-1-238）、AA244-263 （AQP0-1-243）、AA247-263 （AQP0-1-246）、AA250-263 （AQP0-1-249）和AA260-263 （AQP0-1-259）。用免疫染色、荧光标记和细胞器特异性标记研究蛋白表达。通过在爪蟾卵母细胞中表达各自的cRNA并进行渗透肿胀实验来检测Pw。CTCA通过将完整的或突变的AQP0转染到缺乏黏附的l细胞中，并进行细胞聚集和黏附试验来评估。AQP0-1-234和AQP0-1-238没有进入质膜。AQP0-N-del-2-6和AQP0-1-243的转运减少，导致膜Pw和CTCA下降。AQP0-1-246、AQP0-1-249和AQP0-1-259突变体运输正常，功能正常。突变体的Pw和CTCA功能与质膜上AQP0的表达量成正比，与完整AQP0的表达量相当（AQP0-1-263）。翻译后截断N端或c端氨基酸不会改变AQP0的基本透水性或其粘附功能。AQP0可能在不断生长的透镜中起到调节折射率防止球差的作用。类似的研究可以扩展到其他经过翻译后截断的晶状体蛋白，以发现它们如何帮助晶状体保持透明度和平衡，以使物体正确聚焦到视网膜上。
Investigate the impact of natural N- or C-terminal post-translational truncations of lens mature fiber cell Aquaporin 0 (AQP0) on water permeability (Pw) and cell-to-cell adhesion (CTCA) functions. The following deletions/truncations were created by site-directed mutagenesis (designations in parentheses): Amino acid residues (AA) 2–6 (AQP0-N-del-2-6), AA235-263 (AQP0-1-234), AA239-263 (AQP0-1-238), AA244-263 (AQP0-1-243), AA247-263 (AQP0-1-246), AA250-263 (AQP0-1-249) and AA260-263 (AQP0-1-259). Protein expression was studied using immunostaining, fluorescent tags and organelle-specific markers. Pw was tested by expressing the respective cRNA in Xenopus oocytes and conducting osmotic swelling assay. CTCA was assessed by transfecting intact or mutant AQP0 into adhesion-deficient L-cells and performing cell aggregation and adhesion assays. AQP0-1-234 and AQP0-1-238 did not traffic to the plasma membrane. Trafficking of AQP0-N-del-2-6 and AQP0-1-243 was reduced causing decreased membrane Pw and CTCA. AQP0-1-246, AQP0-1-249 and AQP0-1-259 mutants trafficked properly and functioned normally. Pw and CTCA functions of the mutants were directly proportional to the respective amount of AQP0 expressed at the plasma membrane and remained comparable to those of intact AQP0 (AQP0-1-263). Post-translational truncation of N- or C-terminal end amino acids does not alter the basal water permeability of AQP0 or its adhesive functions. AQP0 may play a role in adjusting the refractive index to prevent spherical aberration in the constantly growing lens. Similar studies can be extended to other lens proteins which undergo post-translational truncations to find out how they assist the lens to maintain transparency and homeostasis for proper focusing of objects on to the retina.
登录
查看更多内容
影响因子：
16.8
作者：
Buck, Teresa M.;Wagner, Justin;Skach, William R.
通讯作者：
Skach, William R.
影响因子：
3.4
作者：
Costello, M. J.;Johnsen, Soenke;Balasubramanian, Dorairajan
通讯作者：
Balasubramanian, Dorairajan
影响因子：
7.7
作者：
Buzhynskyy, Nikolay;Hite, Richard K.;Scheuring, Simon
通讯作者：
Scheuring, Simon
影响因子：
11.8
作者：
Aimon, Sophie;Callan-Jones, Andrew;Berthaud, Alice;Pinot, Mathieu;Toombes, Gilman E. S.;Bassereau, Patricia
通讯作者：
Bassereau, Patricia
DOI：
10.1073/pnas.1121054109
发表时间：
2012-06-19
影响因子：
11.1
作者：
Aponte-Santamaria, Camilo;Briones, Rodolfo;de Groot, Bert L.
通讯作者：
de Groot, Bert L.