The human cornea proteome: Bioinformatic analyses indicate importof plasma proteins into the cornea

[摘要] Increased biochemical knowledge of normal and diseased corneas isessential for the understanding of corneal homeostasis andpathophysiology. In a recent study, we characterized the proteome of thenormal human cornea and identified 141 distinct proteins. This datasetrepresents the most comprehensive protein study of the cornea to dateand provides a useful reference for further studies of normal anddiseased human corneas. The list of identified proteins is available atthe Cornea Protein Database. In the present paper, wereview the utilized procedures for extraction and fractionation ofcorneal proteins and discuss the potential roles of the identifiedproteins in relation to homeostasis, diseases, and wound-healing of thecornea. In addition, we compare the list of identified proteins withhigh quality gene expression libraries (cDNA libraries) and SerialAnalysis of Gene Expression (SAGE) data. Of the 141 proteins, 86 (61%)were recognized in cDNA libraries from the corneas of dogs and rabbits,or humans with keratoconus, and 98 (69.5%) were recognized in SAGE dataof mouse and human corneas. However, the percentages of identified genesin each of the protein functional groups differed markedly. Thus,exceptionally few of the traditional blood/plasma proteins and immunedefense proteins that were identified in the human cornea wererecognized in the gene expression libraries of the cornea. Thisobservation strongly indicates that these abundant corneal proteins arenot expressed in the cornea but originate from the surroundingpericorneal tissue.

[学科分类] 生物化学/生物物理