The roles of calcium signaling and ERK1/2 phosphorylation in a Pax6(+/-) mouse model of epithelial wound-healing delay

Lucy J Leiper, Petr Walczysko, Romana Kucerova, Jingxing Ou, Lynne Shanley, Diane Lawson, John V Forrester, Colin D McCaig, Min Zhao, J Martin Collinson

Research output: Contribution to journalArticle

50 Citations (Scopus)
4 Downloads (Pure)

Abstract

Background: Congenital aniridia caused by heterozygousity at the PAX6 locus is associated with ocular surface disease including keratopathy. It is not clear whether the keratopathy is a direct result of reduced PAX6 gene dosage in the cornea itself, or due to recurrent corneal trauma secondary to defects such as dry eye caused by loss of PAX6 in other tissues. We investigated the hypothesis that reducing Pax6 gene dosage leads to corneal wound-healing defects. and assayed the immediate molecular responses to wounding in wild-type and mutant corneal epithelial cells.

Results: Pax6(+/-) mouse corneal epithelia exhibited a 2-hour delay in their response to wounding, but subsequently the cells migrated normally to repair the wound. Both Pax6(+/+) and Pax6(+/-) epithelia activated immediate wound-induced waves of intracellular calcium signaling. However, the intensity and speed of propagation of the calcium wave, mediated by release from intracellular stores, was reduced in Pax6+/- cells. Initiation and propagation of the calcium wave could be largely decoupled, and both phases of the calcium wave responses were required for wound healing. Wounded cells phosphorylated the extracellular signal-related kinases 1/2 (phospho-ERK1/2). ERK1/2 activation was shown to be required for rapid initiation of wound healing, but had only a minor effect on the rate of cell migration in a healing epithelial sheet. Addition of exogenous epidermal growth factor (EGF) to wounded Pax6(+/-) cells restored the calcium wave, increased ERK1/2 activation and restored the immediate healing response to wild-type levels.

Conclusion: The study links Pax6 deficiency to a previously overlooked wound-healing delay. It demonstrates that defective calcium signaling in Pax6+/- cells underlies this delay, and shows that it can be pharmacologically corrected. ERK1/2 phosphorylation is required for the rapid initiation of wound healing. A model is presented whereby minor abrasions, which are quickly healed in normal corneas, transiently persist in aniridic patients, compromising the corneal stroma.

Original languageEnglish
Article number27
Number of pages14
JournalBMC Biology
Volume4
DOIs
Publication statusPublished - 16 Aug 2006

Keywords

  • epidermal-growth-factor
  • metalloproteinase gelatinase B
  • aniridia-related keratopathy
  • homeobox-containing gene
  • mechanical stimulation
  • cell migration
  • gap-junctions
  • segment abnormalities
  • corneal epithelium
  • factor receptor

Cite this

The roles of calcium signaling and ERK1/2 phosphorylation in a Pax6(+/-) mouse model of epithelial wound-healing delay. / Leiper, Lucy J; Walczysko, Petr; Kucerova, Romana; Ou, Jingxing; Shanley, Lynne; Lawson, Diane; Forrester, John V; McCaig, Colin D; Zhao, Min; Collinson, J Martin.

In: BMC Biology, Vol. 4, 27, 16.08.2006.

Research output: Contribution to journalArticle

Leiper, Lucy J ; Walczysko, Petr ; Kucerova, Romana ; Ou, Jingxing ; Shanley, Lynne ; Lawson, Diane ; Forrester, John V ; McCaig, Colin D ; Zhao, Min ; Collinson, J Martin. / The roles of calcium signaling and ERK1/2 phosphorylation in a Pax6(+/-) mouse model of epithelial wound-healing delay. In: BMC Biology. 2006 ; Vol. 4.
@article{23e60e9cf36a427f8adf7425b6f00e20,
title = "The roles of calcium signaling and ERK1/2 phosphorylation in a Pax6(+/-) mouse model of epithelial wound-healing delay",
abstract = "Background: Congenital aniridia caused by heterozygousity at the PAX6 locus is associated with ocular surface disease including keratopathy. It is not clear whether the keratopathy is a direct result of reduced PAX6 gene dosage in the cornea itself, or due to recurrent corneal trauma secondary to defects such as dry eye caused by loss of PAX6 in other tissues. We investigated the hypothesis that reducing Pax6 gene dosage leads to corneal wound-healing defects. and assayed the immediate molecular responses to wounding in wild-type and mutant corneal epithelial cells. Results: Pax6(+/-) mouse corneal epithelia exhibited a 2-hour delay in their response to wounding, but subsequently the cells migrated normally to repair the wound. Both Pax6(+/+) and Pax6(+/-) epithelia activated immediate wound-induced waves of intracellular calcium signaling. However, the intensity and speed of propagation of the calcium wave, mediated by release from intracellular stores, was reduced in Pax6+/- cells. Initiation and propagation of the calcium wave could be largely decoupled, and both phases of the calcium wave responses were required for wound healing. Wounded cells phosphorylated the extracellular signal-related kinases 1/2 (phospho-ERK1/2). ERK1/2 activation was shown to be required for rapid initiation of wound healing, but had only a minor effect on the rate of cell migration in a healing epithelial sheet. Addition of exogenous epidermal growth factor (EGF) to wounded Pax6(+/-) cells restored the calcium wave, increased ERK1/2 activation and restored the immediate healing response to wild-type levels. Conclusion: The study links Pax6 deficiency to a previously overlooked wound-healing delay. It demonstrates that defective calcium signaling in Pax6+/- cells underlies this delay, and shows that it can be pharmacologically corrected. ERK1/2 phosphorylation is required for the rapid initiation of wound healing. A model is presented whereby minor abrasions, which are quickly healed in normal corneas, transiently persist in aniridic patients, compromising the corneal stroma.",
keywords = "epidermal-growth-factor, metalloproteinase gelatinase B, aniridia-related keratopathy, homeobox-containing gene, mechanical stimulation, cell migration, gap-junctions, segment abnormalities, corneal epithelium, factor receptor",
author = "Leiper, {Lucy J} and Petr Walczysko and Romana Kucerova and Jingxing Ou and Lynne Shanley and Diane Lawson and Forrester, {John V} and McCaig, {Colin D} and Min Zhao and Collinson, {J Martin}",
year = "2006",
month = "8",
day = "16",
doi = "10.1186/1741-7007-4-27",
language = "English",
volume = "4",
journal = "BMC Biology",
issn = "1741-7007",
publisher = "BioMed Central",

}

TY - JOUR

T1 - The roles of calcium signaling and ERK1/2 phosphorylation in a Pax6(+/-) mouse model of epithelial wound-healing delay

AU - Leiper, Lucy J

AU - Walczysko, Petr

AU - Kucerova, Romana

AU - Ou, Jingxing

AU - Shanley, Lynne

AU - Lawson, Diane

AU - Forrester, John V

AU - McCaig, Colin D

AU - Zhao, Min

AU - Collinson, J Martin

PY - 2006/8/16

Y1 - 2006/8/16

N2 - Background: Congenital aniridia caused by heterozygousity at the PAX6 locus is associated with ocular surface disease including keratopathy. It is not clear whether the keratopathy is a direct result of reduced PAX6 gene dosage in the cornea itself, or due to recurrent corneal trauma secondary to defects such as dry eye caused by loss of PAX6 in other tissues. We investigated the hypothesis that reducing Pax6 gene dosage leads to corneal wound-healing defects. and assayed the immediate molecular responses to wounding in wild-type and mutant corneal epithelial cells. Results: Pax6(+/-) mouse corneal epithelia exhibited a 2-hour delay in their response to wounding, but subsequently the cells migrated normally to repair the wound. Both Pax6(+/+) and Pax6(+/-) epithelia activated immediate wound-induced waves of intracellular calcium signaling. However, the intensity and speed of propagation of the calcium wave, mediated by release from intracellular stores, was reduced in Pax6+/- cells. Initiation and propagation of the calcium wave could be largely decoupled, and both phases of the calcium wave responses were required for wound healing. Wounded cells phosphorylated the extracellular signal-related kinases 1/2 (phospho-ERK1/2). ERK1/2 activation was shown to be required for rapid initiation of wound healing, but had only a minor effect on the rate of cell migration in a healing epithelial sheet. Addition of exogenous epidermal growth factor (EGF) to wounded Pax6(+/-) cells restored the calcium wave, increased ERK1/2 activation and restored the immediate healing response to wild-type levels. Conclusion: The study links Pax6 deficiency to a previously overlooked wound-healing delay. It demonstrates that defective calcium signaling in Pax6+/- cells underlies this delay, and shows that it can be pharmacologically corrected. ERK1/2 phosphorylation is required for the rapid initiation of wound healing. A model is presented whereby minor abrasions, which are quickly healed in normal corneas, transiently persist in aniridic patients, compromising the corneal stroma.

AB - Background: Congenital aniridia caused by heterozygousity at the PAX6 locus is associated with ocular surface disease including keratopathy. It is not clear whether the keratopathy is a direct result of reduced PAX6 gene dosage in the cornea itself, or due to recurrent corneal trauma secondary to defects such as dry eye caused by loss of PAX6 in other tissues. We investigated the hypothesis that reducing Pax6 gene dosage leads to corneal wound-healing defects. and assayed the immediate molecular responses to wounding in wild-type and mutant corneal epithelial cells. Results: Pax6(+/-) mouse corneal epithelia exhibited a 2-hour delay in their response to wounding, but subsequently the cells migrated normally to repair the wound. Both Pax6(+/+) and Pax6(+/-) epithelia activated immediate wound-induced waves of intracellular calcium signaling. However, the intensity and speed of propagation of the calcium wave, mediated by release from intracellular stores, was reduced in Pax6+/- cells. Initiation and propagation of the calcium wave could be largely decoupled, and both phases of the calcium wave responses were required for wound healing. Wounded cells phosphorylated the extracellular signal-related kinases 1/2 (phospho-ERK1/2). ERK1/2 activation was shown to be required for rapid initiation of wound healing, but had only a minor effect on the rate of cell migration in a healing epithelial sheet. Addition of exogenous epidermal growth factor (EGF) to wounded Pax6(+/-) cells restored the calcium wave, increased ERK1/2 activation and restored the immediate healing response to wild-type levels. Conclusion: The study links Pax6 deficiency to a previously overlooked wound-healing delay. It demonstrates that defective calcium signaling in Pax6+/- cells underlies this delay, and shows that it can be pharmacologically corrected. ERK1/2 phosphorylation is required for the rapid initiation of wound healing. A model is presented whereby minor abrasions, which are quickly healed in normal corneas, transiently persist in aniridic patients, compromising the corneal stroma.

KW - epidermal-growth-factor

KW - metalloproteinase gelatinase B

KW - aniridia-related keratopathy

KW - homeobox-containing gene

KW - mechanical stimulation

KW - cell migration

KW - gap-junctions

KW - segment abnormalities

KW - corneal epithelium

KW - factor receptor

U2 - 10.1186/1741-7007-4-27

DO - 10.1186/1741-7007-4-27

M3 - Article

VL - 4

JO - BMC Biology

JF - BMC Biology

SN - 1741-7007

M1 - 27

ER -