Pax6 regulation in retinal cells by CCCTC binding factor

Area of Science:

• Molecular Biology
• Developmental Biology
• Genetics

Background:

• CCCTC binding factor (CTCF) is known to regulate gene expression during embryonic development.
• Previous studies indicated CTCF's role in regulating the homeobox Pax6 gene, crucial for eye development.

Purpose of the Study:

• To investigate the mechanism by which CTCF controls Pax6 gene expression in human retinoblastoma (Rb) cells.
• To further elucidate CTCF's role in the development of chicken and mouse retinas.

Main Methods:

• Utilized Northern and Western blot analyses to assess CTCF and Pax6 expression in Rb cells.
• Employed Pax6 transcription reporter assays and deletion mutants in Rb cells and chicken embryos.
• Generated CTCF transgenic chicken embryos and mice via lipofection and microinjection for expression analysis.

Main Results:

• Increased CTCF expression correlated with decreased Pax6 expression in Rb cells.
• CTCF interacts with the Pax6 gene's 5'-flanking region, suppressing reporter activity and endogenous expression.
• CTCF knockdown enhanced Pax6 expression, while CTCF overexpression in mouse embryos downregulated retinal Pax6.

Conclusions:

• CTCF plays a significant role in regulating Pax6 expression within retinoblastoma cells.
• CTCF transcriptionally regulates Pax6 in the developing retina, influencing eye development.