Premium
Evolutionary conservation of vertebrate notochord genes in the ascidian Ciona intestinalis
Author(s) -
Kugler Jamie E.,
Passamaneck Yale J.,
Feldman Taya G.,
Beh Jeni,
Regnier Todd W.,
Di Gregorio Anna
Publication year - 2008
Publication title -
genesis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.093
H-Index - 110
eISSN - 1526-968X
pISSN - 1526-954X
DOI - 10.1002/dvg.20403
Subject(s) - notochord , ciona , ciona intestinalis , biology , brachyury , chordate , gene , genetics , vertebrate , transcription factor , microbiology and biotechnology , embryogenesis , embryonic stem cell , mesoderm
To reconstruct a minimum complement of notochord genes evolutionarily conserved across chordates, we scanned the Ciona intestinalis genome using the sequences of 182 genes reported to be expressed in the notochord of different vertebrates and identified 139 candidate notochord genes. For 66 of these Ciona genes expression data were already available, hence we analyzed the expression of the remaining 73 genes and found notochord expression for 20. The predicted products of the newly identified notochord genes range from the transcription factors Ci‐XBPa and Ci‐miER1 to extracellular matrix proteins. We examined the expression of the newly identified notochord genes in embryos ectopically expressing Ciona Brachyury (Ci‐Bra) and in embryos expressing a repressor form of this transcription factor in the notochord, and we found that while a subset of the genes examined are clearly responsive to Ci‐Bra, other genes are not affected by alterations in its levels. We provide a first description of notochord genes that are not evidently influenced by the ectopic expression of Ci‐Bra and we propose alternative regulatory mechanisms that might control their transcription. genesis 46:697–710, 2008. © 2008 Wiley‐Liss, Inc.