Genomic Loci Modulating the Retinal Transcriptome in Wound Healing

摘要

Purpose: The present study predicts and tests genetic networks that modulate gene expression during the retinal wound-healing response. Methods: Upstream modulators and target genes were defined using meta-analysis and bioinfor matic approaches. Quantitative trait loci (QTLs) for retinal acute phase genes (Vazquez-Chona et al. 2005) were defi ned using QTL analysis of CNS gene expression (Chesler et al. 2005). Candidate modulators were defi ned using computational analysis of gene and motif sequences. The effect of candidate genes on wound healing was tested using animal models of gene expression. Results: A network of early wound-healing genes is modulated by a locus on chromosome 12. The genetic background of the locus altered the wound-healing response of the retina. The C57BL/6 allele conferred enhanced expression of neuronal marker Thy1 and heat-shock-like crystallins, whereas the DBA/2J allele correlated with greater levels of the classic marker of retinal stress, glial fibrillary acidic protein (GFAP). Id2 and Lpin1 are candidate upstream modula tors as they strongly correlated with the segregation of DBA/2J and C57BL/6 alleles, and their dosage levels correlated with the enhanced expression of survival genes (Thy1 and crystallin genes). Conclusion: We defined a genetic network associated with the retinal acute injury response. Using genetic linkage analysis of natural transcript variation, we identified regulatory loci and candidate modulators that control transcript levels of acute phase genes. Our results support the convergence of gene expression profiling, QTL analysis, and bioinformatics as a rational approach to discover molecular pathways controlling retinal wound healing.