Hsf4 knockout mouse lacks lens-specific αA-crystallin modification. (A) 2D electrophoresis map of lens proteins of 8-week-old Hsf4-/- and Hsf4+/+ mice. There are obvious differences between the two 2D gels in the boxed regions. The most different intensity dots between Hsf4-/- and Hsf4+/+ mice are indicated with red circles. (B) High-resolution images of boxed regions in panel A images showing loss of posttranslational modification αA-crystallin spots in the lenses of Hsf4-/- mice. In Hsf4-/- mice, some αA-crystallin truncated fragments were missing in the 2D gel. Proteins were identified by LC/MS sequencing. The arrows point to the truncated αA-crystallins. (C) Real-time PCR determining mRNA levels of calpain2 and Lp82 in newborn and adult wild-type and Hsf4 knockout mice.