Transient cardiac expression of the tinman-family homeobox gene, XNkx2-10.
In Drosophila, the tinman homeobox gene is absolutely required for heart development. In the vertebrates, a small family of tinman-related genes, the cardiac NK-2 genes, appear to play a similar role in the formation of the vertebrate heart. However, targeted gene ablation of one of these genes, Nkx2-5, results in defects in only the late stages of cardiac development suggesting the presence of a rescuing gene function early in development. Here, we report the characterization of a novel tinman-related gene, XNkx2-10, which is expressed during early heart development in Xenopus. Using in vitro assays, we show that XNkx2-10 is capable of transactivating expression from promoters previously shown to be activated by other tinman-related genes, including Nkx2-5. Furthermore, Xenopus Nkx2-10 can synergize with the GATA-4 and SRF transcription factors to activate reporter gene expression.
Newman
C S
CS
Division of Molecular Cell and Developmental Biology, School of Biological Sciences, University of Texas at Austin, Austin 78712, USA.
Reecy
J
J
Grow
M W
MW
Ni
K
K
Boettger
T
T
Kessel
M
M
Schwartz
R J
RJ
Krieg
P A
PA
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018076:DNA, Complementary; D029721:Drosophila Proteins; D015870:Gene Expression; D006321:Heart / Q000196:embryology*; D018398:Homeodomain Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D012097:Repressor Proteins / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D015534:Trans-Activators / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics*; D014981:Xenopus / Q000196:embryology / Q000235:genetics; D029867:Xenopus Proteins
D018076:DNA, Complementary; D029721:Drosophila Proteins; D018398:Homeodomain Proteins; C409765:NKX2-6 protein, Xenopus; D012097:Repressor Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D029867:Xenopus Proteins; C102933:tin protein, Drosophila