Organizing axes in time and space; 25 years of colinear tinkering.
During vertebrate development, clustered genes from the Hox family of transcription factors are activated in a precise temporal and spatial sequence that follows their chromosomal order (the "Hox clock"). Recent advances in the knowledge of the underlying mechanisms reveal that the embryo uses a variety of strategies to implement this colinear process, depending on both the type and the evolutionary history of axial structures. The search for a universal mechanism has likely hampered our understanding of this enigmatic phenomenon, which may be caused by various and unrelated regulatory processes, as long as the final distribution of proteins (the HOX code) is preserved.
Kmita
Marie
M
Department of Zoology and Animal Biology and National Center of Competence in Research "Frontiers in Genetics," University of Geneva, Sciences III, Quai Ernest Ansermet 30, 1211 Geneva 4, Switzerland.
Duboule
Denis
D
D000818:Animals; D001683:Biological Clocks / Q000502:physiology*; D019521:Body Patterning; D047108:Embryonic Development; D005314:Embryonic and Fetal Development; D018507:Gene Expression Regulation, Developmental; D005801:Genes, Homeobox; D018398:Homeodomain Proteins / Q000235:genetics / Q000502:physiology*; D008954:Models, Biological; D005810:Multigene Family; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*; D014714:Vertebrates / Q000196:embryology* / Q000235:genetics / Q000378:metabolism
D018398:Homeodomain Proteins; D014157:Transcription Factors