Developmental Biology

1. Cellular and Molecular Mechanisms
   1. Gene expression
      1. Transcriptional regulation
         1. Transcription factors
            1. Basic helix-loop-helix (bHLH) factors
            2. Zinc finger proteins
            3. Homeodomain proteins
         2. Promoter and enhancer elements
         3. RNA polymerase complexes
         4. Transcriptional activators and repressors
      2. Epigenetic modifications
         1. DNA methylation
            1. CpG islands and gene silencing
            2. Role in tissue-specific gene expression
         2. Histone modifications
            1. Acetylation, methylation, and phosphorylation
            2. Impact on chromatin structure and gene accessibility
         3. Chromatin remodeling complexes
            1. SWI/SNF and other chromatin remodeling families
         4. Non-coding RNAs
            1. Role of microRNAs in post-transcriptional regulation
            2. Long non-coding RNAs in gene expression regulation
   2. Signal transduction pathways
      1. Role of growth factors
         1. Types of growth factors (e.g., EGF, FGF, VEGF)
         2. Mechanisms of action and receptor binding
         3. Downstream signaling cascades
      2. Notch signaling pathway
         1. Components and receptors
         2. Role in cell fate decisions
         3. Lateral inhibition and boundary formation
      3. Wnt signaling pathway
         1. Canonical and non-canonical pathways
         2. Beta-catenin regulation
         3. Role in embryogenesis and stem cell maintenance
      4. Hedgehog signaling pathway
         1. Sonic, Indian, and Desert Hedgehog proteins
         2. Glide and Smoothened interactions
         3. Role in patterning and organogenesis
      5. TGF-beta signaling pathway
         1. SMAD protein mediators
         2. Role in tissue homeostasis and development
         3. Crosstalk with other pathways
   3. Cell interactions and adhesion
      1. Cadherins
         1. Role in cell-cell adhesion and communication
         2. E-cadherin in epithelial tissue formation
         3. Cadherin-catenin complex in signaling pathways
      2. Integrins
         1. Role in cell-matrix interactions
         2. Influence on cell motility and structure
         3. Signaling pathways transduced by integrins
      3. Extracellular matrix (ECM)
         1. ECM components (collagens, fibronectins, laminins)
         2. ECM remodeling enzymes (MMPs)
         3. Influence on cell behavior and tissue architecture
      4. Cell junctions
         1. Tight junctions and the regulation of barrier function
         2. Gap junctions and intercellular communication
         3. Desmosomes and structural integrity of tissues