Disease relevance of Dromaiidae

• Mice carrying Myc(His) just 5' of the intronic heavy-chain enhancer Emu (strain iMyc(Emu)) provide a specific model of the type of T(12;15) found in a subset (approximately 20%) of plasmacytomas that develop "spontaneously" in the gut-associated lymphoid tissue (GALT) of interleukin-6 transgenic BALB/c (C) mice [1].
• Corroborating these findings, in vivo Emu; K cyclin expression cooperates with p53 loss in the induction of lymphomas [2].

High impact information on Dromaiidae

• To examine the role of p21ras in the development of B lymphocytes, we generated transgenic mice expressing a dominant-negative form of Ras in B lymphocyte progenitors, using a novel transcriptional element consisting of the Emu enhancer and the lck proximal promoter [3].
• DNA sequence comparisons between a CR1 element isolated from a sarus crane (Grus antigone) and those isolated from an emu (Dromaius novaehollandiae) showed that two short highly conserved regions are present [4].
• When the 3'KE/Bcl-XL mouse was crossed to an Emu/c-Myc transgenic mouse, median survival of double transgenic progeny was 5.5 weeks [5].
• Cotransfection with Cux/CDP represses the activity of Emu via the MAR sequences in both B and non-B cells [6].
• To elucidate the roles of PD(Q52) and Emu in the regulation of IgH locus accessibility, we generated mice with targeted deletions of these elements [7].

Biological context of Dromaiidae

• High level expression in mice of transgenes derived from the immunoglobulin heavy chain (IgH) locus requires both the core enhancer (Emu) and the matrix attachment regions (MARs) that flank Emu [8].
• In addition to the intron enhancer, Emu, there is a complex regulatory region 3' of the Calpha gene, which spans approximately 40 kb and contains several enhancers [9].
• However, upon transfection into fish or mouse lymphocytes, it activates transcription to an extent equivalent to that of the mouse IgH intronic enhancer (Emu) [10].
• Intravenous pharmacokinetics of penicillin G and antipyrine in ostriches (Struthio camelus) and emus (Dromaius novaehollandiae) [11].

Associations of Dromaiidae with chemical compounds

• In Dromaius novaehollandiae (emu), a progressive neurologic disease was recently discovered, which was characterized by NAGLU deficiency and heparan sulfate accumulation [12].
• Photoperiodic control of the concentration of luteinizing hormone, prolactin and testosterone in the male emu (Dromaius novaehollandiae), a bird that breeds on short days [13].
• Penicillin G and antipyrine, which served as model drugs to assess the relative capacities of renal and hepatic elimination pathways, respectively, were each administered intravenously to six ostriches (Struthio camelus) and to six emus (Dromaius novaehollandiae) [11].
• Disposition of single-dose intravenously administered amikacin in emus (Dromaius novaehollandiae) [14].
• Disposition of single-dose intravenously administered enrofloxacin in emus (Dromaius novaehollandiae) [15].

Gene context of Dromaiidae

• As cyclin D1 mutants that are refractory to nuclear export display heighten oncogenicity in vitro compared with WT D1, we generated mice expressing FLAG-D1/T286A, a constitutively nuclear mutant, under the control of the immunoglobulin enhancer, Emu [16].
• We suggest a model whereby Emu/MARS enhances mitotic GC at the endogenous IgH mu locus by effecting chromatin modifications in adjacent DNA [17].
• This confirms previous results obtained with chromosomally integrated substrates, except for the finding that the full length 3' MAR of Emu stimulates V(D)J recombination in an episomal but not in a chromosomal context [18].
• The same observation was made in the rhea and in the newly sequenced NADH3 gene of the emu, Dromaius novaehollandiae [19].
• To define the potential role of Emu plus MAR in class switch recombination (CSR), we generated IgG-expressing hybridomas from B cells heterozygous for mutations that delete all of these elements or replace them with a neo(r) gene and analyzed the switch status of the mutated IgH loci [20].

References