Sequence and peptide map of guinea pig aquaporin 0

[摘要] Purpose: Hyperbaric oxygen-treated guinea pigs serve as a usefulanimal model of nuclear cataract. To understand the structure andfunction of major intrinsic proteins in this model, the primary sequenceand major posttranslational modifications to guinea pig aquaporin 0(AQP0) were determined.Methods: The cDNA encoding guinea pig AQP0 was amplified by PCR,cloned and sequenced. After protein enrichment from guinea pig lenstissue, the protein sequence and the posttranslational modifications toAQP0 were determined by using combined chemical cleavage, trypsin andpepsin digestion with matrix assisted laser desorption/ionization massspectrometry or capillary liquid chromatography tandem massspectrometry.Results: The primary structure of AQP0 was determined from the DNAsequence and the translated sequence confirmed by mass spectrometry.Serine 235 was identified to be the major phosphorylation site.Conclusions: Significant sequence homology was observed betweenspecies including putative regulatory sites of phosphorylation and pHregulation. These data form a foundation of information from which tobegin assessing posttranslational modifications in cataract models.

[学科分类] 生物化学/生物物理