DNA-binding characteristics of cnidarian Pax-C and Pax-B proteins in vivo and in vitro: no simple relationship with the Pax-6 and Pax-2/5/8 classes.
Cnidarians are the simplest animals in which distinct eyes are present. We have previously suggested that cnidarian Pax-Cam might represent a precursor of the Pax-6 class. Here we show that when expressed in Drosophila imaginal discs, Pax-Cam chimeric proteins containing the C-terminal region of EY were capable of eye induction and driving expression of a reporter gene under the control of a known EY target (the sine oculis gene). Whilst these results are consistent with a Pax-6-like function for Pax-Cam, in band shift experiments we were unable to distinguish the DNA-binding behaviour of the Pax-Cam Paired domain from that of a second Acropora Pax protein, Pax-Bam. The ability of a Pax-Bam/EY chimera to also induce eye formation in leg imaginal discs, together with the in vitro data, cast doubt on previously assumed direct relationships between cnidarian Pax genes and the Pax-6 and Pax-2/5/8 classes of bilateral animals.
D000818:Animals; D037421:Anthozoa / Q000235:genetics*; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics*; D029721:Drosophila Proteins / Q000235:genetics* / Q000502:physiology; D004627:Embryonic Induction / Q000235:genetics; D005123:Eye / Q000196:embryology; D005136:Eye Proteins / Q000502:physiology; D015870:Gene Expression / Q000235:genetics*; D018398:Homeodomain Proteins / Q000737:chemistry* / Q000235:genetics / Q000502:physiology; D066298:In Vitro Techniques; D009024:Morphogenesis / Q000235:genetics; D009687:Nuclear Proteins; D051762:PAX2 Transcription Factor; D051757:PAX5 Transcription Factor; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors; D011993:Recombinant Fusion Proteins / Q000235:genetics*; D012097:Repressor Proteins; D015534:Trans-Activators / Q000737:chemistry / Q000235:genetics; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics
D017931:DNA Primers; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D005136:Eye Proteins; D018398:Homeodomain Proteins; D009687:Nuclear Proteins; D051762:PAX2 Transcription Factor; D051757:PAX5 Transcription Factor; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors; C414094:Pax-B protein, Podocoryne carnea; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; C087345:So protein, Drosophila; D015534:Trans-Activators; D014157:Transcription Factors; C113278:ey protein, Drosophila