Induction of altered gene expression in early embryos

Area of Science:

• Developmental Biology
• Toxicology
• Genetics

Background:

• Teratogens can disrupt embryogenesis by altering positional information, which is crucial for establishing body axes (anterior-posterior, dorsal-ventral, left-right).
• Genes encoding transcription factors are key in regulating positional information and can be affected by teratogens, leading to abnormal development.
• Teratogens can also directly impact cell differentiation, proliferation, and apoptosis, processes regulated by signaling molecules like growth factors and retinoids.

Purpose of the Study:

• To review known genes perturbed by teratogens during early embryogenesis (preorganogenesis).
• To discuss how teratogens modify positional information and affect gene expression.
• To describe methods for identifying genes altered by teratogen exposure.

Main Methods:

• Literature review of studies on teratogen effects on gene expression during embryogenesis.
• Analysis of gene regulatory networks involved in establishing body axes.
• Overview of techniques for identifying differentially expressed genes in response to teratogens.

Main Results:

• Teratogens perturb gene expression controlling primary body axes and cell fate.
• Disruption of signaling pathways by teratogens can lead to aberrant tissue differentiation and morphogenesis.
• Teratogens can interact synergistically or antagonistically, further complicating developmental outcomes.

Conclusions:

• Understanding teratogen-induced gene expression changes is vital for preventing developmental abnormalities.
• Identifying affected genes provides insights into critical developmental pathways and potential therapeutic targets.
• Advanced techniques are essential for discovering novel genes critical for development that are impacted by teratogens.