title: Fins into limbs: Autopod acquisition and anterior elements reduction by modifying gene networks involving 5'Hox, Gli3, and Shh.
abstract: Two major morphological changes occurred during the fin-to-limb transition: the appearance of the autopod, and the reduction of anterior skeletal elements. In the past decades, numerous approaches to the study of genetic developmental systems involved in patterning of fins/limbs among different taxa have provided clues to better understand the mechanism of the fin-to-limb transition. In this article, I discuss recent progress toward elucidating the evolutionary origin of the autopod and the mechanism through which the multiple-basal bones of ancestral fins were reduced into a single bone (humerus/femur). A particular focus of this article is the patterning mechanism of the tetrapod limb and chondrichthyan fin controlled by gene networks involving the 5'Hox genes, Gli3 and Shh. These recent data provide possible scenarios that could have led to the transformation of fins into limbs.
authors.affiliation: Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, B-17, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan. Electronic address: mitanaka@bio.titech.ac.jp.
authors.forename: Mikiko
authors.initials: M
authors.lastname: Tanaka
mesh_terms: D058500:Animal Fins / Q000502:physiology*; D000818:Animals; D005075:Biological Evolution; D019521:Body Patterning; D001842:Bone and Bones; D019143:Evolution, Molecular; D005121:Extremities / Q000502:physiology*; D005399:Fishes; D018507:Gene Expression Regulation, Developmental; D053263:Gene Regulatory Networks; D005801:Genes, Homeobox; D053823:Hedgehog Proteins / Q000378:metabolism*; D018398:Homeodomain Proteins / Q000378:metabolism*; D005810:Multigene Family; D014157:Transcription Factors / Q000378:metabolism*; D029961:Zebrafish Proteins / Q000378:metabolism*; D000074290:Zinc Finger Protein Gli3
chemical_list: C560095:Gli3 protein, zebrafish; D053823:Hedgehog Proteins; D018398:Homeodomain Proteins; C524053:Shha protein, zebrafish; D014157:Transcription Factors; D029961:Zebrafish Proteins; D000074290:Zinc Finger Protein Gli3
keywords: Anterior-posterior patterning; Autopod origin; Fin-to-limb transition; Multiple-basal fin