Hoxc gene collinear expression and epigenetic modifications established during embryogenesis are maintained until...

Area of Science:

• Developmental Biology
• Epigenetics
• Genetics

Background:

• Hox genes are critical for anterior-posterior body axis formation in vertebrate embryos.
• Histone methylation patterns correlate with Hox gene expression collinearity.
• Histone modifications are hypothesized to mechanistically regulate Hox gene expression patterns.

Purpose of the Study:

• To investigate the maintenance of spatial collinear Hoxc gene expression patterns.
• To examine the persistence of associated histone modifications during embryogenesis and early postnatal development.
• To understand the epigenetic regulation of body axis patterning.

Main Methods:

• Semi-quantitative RT-PCR was used to analyze Hoxc gene expression patterns.
• Chromatin immunoprecipitation (ChIP)-PCR was employed to assess histone modifications.
• Analysis was conducted on mouse embryos (E8.5-E14.5) and early postnatal mice (P5).

Main Results:

• Spatiotemporal expression patterns of Hoxc genes were maintained from embryonic day 8.5 through postnatal day 5.
• H3K27me3 showed a weak correlation with Hoxc gene expression in trunk regions, diminishing over time.
• H3K4me3 enrichment strongly correlated with Hoxc gene expression at both embryonic and postnatal stages.

Conclusions:

• The spatiotemporal collinear expression of Hoxc genes and their epigenetic modifications are maintained after birth.
• These epigenetic mechanisms likely contribute to establishing and maintaining the gene expression code for positional information along the body axis.
• This epigenetic memory plays a role in lifelong organismal patterning.