BIOL 202 Lecture Notes - Lecture 25: Ultrabithorax, Hox Gene, Zygote
Document Summary
Regulation of eve (even-skip gene) transcription in stripe 2 stripe 2 will have spec. conc. of maternally loaded zygotic factors: high [hb-z, medium [bcd, low [gt], [kr] Regulation of eve expression is facilitated via combinations fo tfs, both maternal-effect and gap genes. Each enhancer has a different combination of binding sites. Establishment of segmentation domains: segment polarity genes segment polarity genes: encode components of two cell-cell signaling pathways. Receptors, tfs: activated/repressed by pair-rule genes, function to define a and p within each segment, mutants have mirroring of one half of each segment. The timing of zygotic transcription plays a role in the phenotype of the offspring. Transcription within the first 3 hours of transcription is determined by maternally loaded genes, no zygotic transcription w/in first 3 hours. Maternal-effect genes: define anterior (bicoid)/posterior (nanos, hb-m) Gap genes: divide a-p axis into broad domains (hb-z)
