In Drosophila, the erect wing (ewg) protein is required for proper development of the central nervous system and the indirect flight muscles. The fly ewg gene encodes a novel DNA-binding domain that is also found in four genes previously identified in sea urchin, chicken, zebrafish, and human [1]. Nuclear respiratory factor-1 is a transcriptional activator that has been implicated in the nuclear control of respiratory chain expression in vertebrates. The first 26 amino acids of nuclear respiratory factor-1 are required for the binding of dynein light chain. The interaction with dynein light chain is observed for both ewg and Nrf-1, transcription factors that are structurally and functionally similar between humans and Drosophila [2]. The highest level of expression of both ewg and Nrf-1 was found in the central nervous system, somites, first branchial arch, optic vesicle, and otic vesicle. In the mouse Nrf-1 protein, Swiss-Prot:Q8C4C0, there is also an NLS domain at 88-116, and a DNA binding and dimerisation domain at 127-282. Ewg is a site-specific transcriptional activator, and evolutionarily conserved regions of ewg contribute both positively and negatively to transcriptional activity [3].

1: Coding sequence, chromosomal localization, and expression pattern of Nrf1: the mouse homolog of Drosophila erect wing. Schaefer L, Engman H, Miller JB; Mamm Genome. 2000;11:104-110. PMID:10656923

2: Dynein light chain interacts with NRF-1 and EWG, structurally and functionally related transcription factors from humans and drosophila. Herzig RP, Andersson U, Scarpulla RC; J Cell Sci. 2000;113:4263-4273. PMID:11069771

3: Conserved regions of the Drosophila erect wing protein contribute both positively and negatively to transcriptional activity. Fazio IK, Bolger TA, Gill G; J Biol Chem. 2001;276:18710-18716. PMID:11278998