he consequences of arrest can be catastrophic if the gene being transcribed is essential as no product will be made by the arrested polymerase, and that same enzyme will cause a roadblock to other polymerases attempting to transcribe the same gene.The cell has machinery that removes the arrested polymerase and at the same time recruits repair enzymes (in particular, the endonuclease Uvr(A)BC); the repair that follows is called transcription-coupled repair. Both polymerase removal and repair enzyme recruitment are performed by a single protein called TRCF.

#Id: 7371

#Unit 5. Developmental Biology

#Id: 7372

#Unit 5. Developmental Biology

Major genes affecting segmentation pattern 

1.Gap genes                 2. Pair rule genes(primary)           3. Segment polarity genes      

Kruppel (Kr)                    hairy(h)                                             engrailed (en)

knirps (kni)                      even skipped(eve)                           wingless (wg)

hunchback (hb)              runt(run)                                           cubitus interruptus(ci) 

giant (gt)                          Pair rule genes (secondary)           hedgehog(hh)

tailless (til)                       fushi tarazu (ftz)                              fused (fu)

huckebein (hkb)              odd paired (opa)                             armadillo (arm)

buttonhead (btd)            odd skipped (odd)                          patched (ptc)

empty spiracles (ems)    sloppy paired (slp)                          gooseberry (gsb)

orthodenticle (otd)         paired (prd)                                      pangolin (pan

#Id: 7373

#Unit 5. Developmental Biology

#Id: 7374

#Unit 5. Developmental Biology

#Id: 7375

#Unit 5. Developmental Biology

#Id: 7376

#Unit 5. Developmental Biology