The expression pattern of the subunit of chaperonin containing T-complex polypeptide 1 and its substrate, alpha-smooth muscle actin, during corneal wound healing.
OBJECTIVE
This study was designed to demonstrate the expression of the chaperonin containing T-complex polypeptide 1 (CCT) and alpha-smooth muscle actin (alpha-SMA), in normal corneas and corneas treated with ultraviolet radiation (UVR). The wound model chosen is previously characterized, the injury is mild and the cornea heals to transparency.


METHODS
Rabbit corneas were exposed to UVR at the dose producing keratitis. The corneas were allowed to heal for up to 5 days and the paraffin-embedded tissue specimens were double stained and examined morphologically and immunohistochemically. Expression of CCT and alpha-SMA genes was investigated by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR).


RESULTS
There was a front of repopulating keratocytes that showed positive staining for alpha-SMA after 3 days. The alpha-SMA mRNA was already strongly expressed after 1 day, whereas the expression level of CCT was increased after 2 days. After 5 days the levels were decreased. By this time the stroma was partly repopulated by keratocytes.


CONCLUSIONS
In a mild wound, the expression of alpha-SMA mRNA is followed by expression of mRNA of at least one subunit of the complex folding alpha-SMA. At protein level, alpha-SMA is detected in the front line of repopulating keratocytes. Expression levels for both mRNAs decline as the stroma repopulation process progresses.
Koulikovska
Marina
M
Department of Ophthalmology, Linköping University Hospital, Linköping, Sweden. mark@ste.ki.se
Podskochy
Alexander
A
Fagerholm
Per
P
D000199:Actins / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D056404:Chaperonin Containing TCP-1; D018833:Chaperonins / Q000235:genetics* / Q000378:metabolism; D003315:Cornea / Q000378:metabolism / Q000528:radiation effects*; D005260:Female; D005347:Fibroblasts / Q000378:metabolism; D005786:Gene Expression Regulation; D007124:Immunoenzyme Techniques; D012333:RNA, Messenger / Q000378:metabolism; D011817:Rabbits; D011833:Radiation Injuries, Experimental / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014466:Ultraviolet Rays; D014945:Wound Healing
D000199:Actins; D012333:RNA, Messenger; D056404:Chaperonin Containing TCP-1; D018833:Chaperonins