Pitx homeobox genes in Ciona and amphioxus show left-right asymmetry is a conserved chordate character and define the ascidian adenohypophysis.

All vertebrates have directional asymmetries in the organization of their internal organs. In jawed vertebrates, development of asymmetry is controlled by a conserved molecular pathway that includes Pitx2, which is expressed by lateral plate mesoderm cells on the left side of the embryo. Pitx2 is a...

Full description

Bibliographic Details
Main Authors: Boorman, C, Shimeld, S
Format: Journal article
Language:English
Published: 2002
_version_ 1797067385118654464
author Boorman, C
Shimeld, S
author_facet Boorman, C
Shimeld, S
author_sort Boorman, C
collection OXFORD
description All vertebrates have directional asymmetries in the organization of their internal organs. In jawed vertebrates, development of asymmetry is controlled by a conserved molecular pathway that includes Pitx2, which is expressed by lateral plate mesoderm cells on the left side of the embryo. Pitx2 is a member of the Pitx homeobox gene family, the expression of which also marks stomodeal ectoderm and the adenohypophysis. Here we report the characterization of Pitx genes from Branchiostoma floridae (an amphioxus) and Ciona intestinalis (a urochordate), representatives of two basal chordate lineages and successively deeper outgroups to the vertebrates. Expression of B. floridae Pitx is similar to that reported from B. belcheri, a different amphioxus species. Expression of the Ciona Pitx ortholog in the embryonic primordial pharynx and adult neural complex leads us to propose the Ciona primordial pharynx and ciliated funnel are homologous to the adenohypophyseal placode and adenohypophysis, respectively. Additionally, in both species we identify asymmetrical left-sided expression of Pitx genes during embryonic development. This shows that asymmetrical Pitx gene expression, and by inference directional asymmetry, evolved before the radiation of living chordates and should be considered a chordate character.
first_indexed 2024-03-06T21:55:32Z
format Journal article
id oxford-uuid:4ccb4148-0294-4bd2-b19d-9355326306b2
institution University of Oxford
language English
last_indexed 2024-03-06T21:55:32Z
publishDate 2002
record_format dspace
spelling oxford-uuid:4ccb4148-0294-4bd2-b19d-9355326306b22022-03-26T15:51:36ZPitx homeobox genes in Ciona and amphioxus show left-right asymmetry is a conserved chordate character and define the ascidian adenohypophysis.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:4ccb4148-0294-4bd2-b19d-9355326306b2EnglishSymplectic Elements at Oxford2002Boorman, CShimeld, SAll vertebrates have directional asymmetries in the organization of their internal organs. In jawed vertebrates, development of asymmetry is controlled by a conserved molecular pathway that includes Pitx2, which is expressed by lateral plate mesoderm cells on the left side of the embryo. Pitx2 is a member of the Pitx homeobox gene family, the expression of which also marks stomodeal ectoderm and the adenohypophysis. Here we report the characterization of Pitx genes from Branchiostoma floridae (an amphioxus) and Ciona intestinalis (a urochordate), representatives of two basal chordate lineages and successively deeper outgroups to the vertebrates. Expression of B. floridae Pitx is similar to that reported from B. belcheri, a different amphioxus species. Expression of the Ciona Pitx ortholog in the embryonic primordial pharynx and adult neural complex leads us to propose the Ciona primordial pharynx and ciliated funnel are homologous to the adenohypophyseal placode and adenohypophysis, respectively. Additionally, in both species we identify asymmetrical left-sided expression of Pitx genes during embryonic development. This shows that asymmetrical Pitx gene expression, and by inference directional asymmetry, evolved before the radiation of living chordates and should be considered a chordate character.
spellingShingle Boorman, C
Shimeld, S
Pitx homeobox genes in Ciona and amphioxus show left-right asymmetry is a conserved chordate character and define the ascidian adenohypophysis.
title Pitx homeobox genes in Ciona and amphioxus show left-right asymmetry is a conserved chordate character and define the ascidian adenohypophysis.
title_full Pitx homeobox genes in Ciona and amphioxus show left-right asymmetry is a conserved chordate character and define the ascidian adenohypophysis.
title_fullStr Pitx homeobox genes in Ciona and amphioxus show left-right asymmetry is a conserved chordate character and define the ascidian adenohypophysis.
title_full_unstemmed Pitx homeobox genes in Ciona and amphioxus show left-right asymmetry is a conserved chordate character and define the ascidian adenohypophysis.
title_short Pitx homeobox genes in Ciona and amphioxus show left-right asymmetry is a conserved chordate character and define the ascidian adenohypophysis.
title_sort pitx homeobox genes in ciona and amphioxus show left right asymmetry is a conserved chordate character and define the ascidian adenohypophysis
work_keys_str_mv AT boormanc pitxhomeoboxgenesincionaandamphioxusshowleftrightasymmetryisaconservedchordatecharacteranddefinetheascidianadenohypophysis
AT shimelds pitxhomeoboxgenesincionaandamphioxusshowleftrightasymmetryisaconservedchordatecharacteranddefinetheascidianadenohypophysis