Methylation status of the putative Pax6 promoter in olive ridley sea turtle embryos with eye defects: An initial approach

Publication date: Available online 12 August 2018Source: Mechanisms of DevelopmentAuthor(s): Rodolfo Martín-del-Campo, Annelisse Bárcenas-Ibarra, Itzel Sifuentes-Romero, Raúl Llera-Herrera, Alejandra García-GascaAbstractNormal development involves the interplay of genetic and epigenetic regulatory mechanisms. Pax6 is an eye-selector factor responsible for initiating the regulatory cascade for the development of the eyes. For the olive ridley sea turtle (Lepidochelys olivacea), a threatened species, eye malformations have been reported. In order to study the DNA methylation status of the putative promoter of the Pax6 gene in embryos with ocular malformations, an exploratory study was carried out in which DNA was isolated from embryos with anophthalmia, microphthalmia, and cyclopia, as well as from their normal counterparts. The 5′-flanking region from the Pax6 gene was isolated, showing two CpG islands (CGIs). The methylation status of CGIs in malformed embryos was compared with that of normal embryos by bisulfite sequencing. Putative transcription factor binding sites and regulatory features were identified. Methylation patterns were observed in both CpG and non-CpG contexts, and were unique for each malformed embryo; in the CpG context, an embryo with cyclopia showed a methylated cytosine upstream the CGI-1 not present in other embryos, an embryo with left anophthalmia presented two methylated cytosines in the CGI-1, whereas an embryo with left anophthalmia and right m...
Source: Mechanisms of Development - Category: Biology Source Type: research