Genetics, Vol 140, 183-192, Copyright © 1995


INVESTIGATIONS

Genotypic Effects, Maternal Effects and Grand-Maternal Effects of Immobilized Derivatives of the Transposable Element mariner

A. R. Lohe, D. A. Lidholm and D. L. Hartl
Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138

The baseline rate of spontaneous integration of the autonomous mariner element Mos1 into the germline of Drosophila melanogaster is estimated as 16 +/- 5% (mean +/- SE) among fertile G0 flies. However, the transformation rate is reduced ~20-fold in Mos1 constructs with exogenous DNA in the size range 5-12 kb inserted into the SacI site. To provide alternative Mos1 helper plasmids for transformation experiments, two types of Mos1-promoter fusions were constructed: hsp-70:Mos1 and hsp26-Sgs3:Mos1. The former has the Mos1 coding region driven by the hsp70 heat-shock promoter; the latter has it driven by the basal Sgs3 promoter under the control of the hsp26 female-germline specific transcriptional regulator. When introduced into D. melanogaster by P-element-mediated germline transformation, these elements are unable to transpose or excise in the presence of autonomous Mos1-related elements (they are ``marooned'') because the 5' inverted repeat of Mos1 is missing. As expected, the hsp26-Sgs3:Mos1 fusions exhibit a significantly greater rate of germline excision of a target mariner element than do the hsp70:Mos1 fusions. Unexpectedly, the rate of excision of target mariner elements induced by hsp26-Sgs3:Mos1 is the same in the male germline as in the female germline. Both hsp:Mos1 fusions show strong germline expression and a maternal effect of the mariner transposase. A significant grand-maternal effect of the hsp:Mos1 fusions was also detected as a result of a maternal effect on the germline of the F(1) progeny. Among flies carrying the promoter fusions inherited maternally, about three-quarters of the overall rate of germline excision derives from the direct genotypic effect and about one-quarter results from the grand-maternal effect. Despite the strong somatic expression of the hsp:Mos1 fusions, mariner transformants carrying a white(+) reporter gene at the SacI site remained stable in the soma.


This article has been cited by other articles:


Home page
J. Exp. Biol.Home page
D. A. O'Brochta, N. Sethuraman, R. Wilson, R. H. Hice, A. C. Pinkerton, C. S. Levesque, D. K. Bideshi, N. Jasinskiene, C. J. Coates, A. A. James, et al.
Gene vector and transposable element behavior in mosquitoes
J. Exp. Biol., November 1, 2003; 206(21): 3823 - 3834.
[Abstract] [Full Text] [PDF]


Home page
GeneticsHome page
A. R. Lohe and D. L. Hartl
Efficient Mobilization of mariner in Vivo Requires Multiple Internal Sequences
Genetics, February 1, 2002; 160(2): 519 - 526.
[Abstract] [Full Text] [PDF]


Home page
GeneticsHome page
E. R. Lozovsky, D. Nurminsky, E. A. Wimmer, and D. L. Hartl
Unexpected Stability of mariner Transgenes in Drosophila
Genetics, February 1, 2002; 160(2): 527 - 535.
[Abstract] [Full Text] [PDF]


Home page
GeneticsHome page
D. L. Hartl
Discovery of the Transposable Element Mariner
Genetics, February 1, 2001; 157(2): 471 - 476.
[Full Text]


Home page
GeneticsHome page
A. R. Lohe, C. Timmons, I. Beerman, E. R. Lozovskaya, and D. L. Hartl
Self-Inflicted Wounds, Template-Directed Gap Repair and a Recombination Hotspot: Effects of the mariner Transposase
Genetics, February 1, 2000; 154(2): 647 - 656.
[Abstract] [Full Text]


Home page
Proc. Natl. Acad. Sci. USAHome page
G. Luo, Z. Ivics, Z. Izsvak, and A. Bradley
Chromosomal transposition of a Tc1/mariner-like element in mouse embryonic stem cells
PNAS, September 1, 1998; 95(18): 10769 - 10773.
[Abstract] [Full Text] [PDF]


Home page
Proc. Natl. Acad. Sci. USAHome page
J. M. Fadool, D. L. Hartl, and J. E. Dowling
Transposition of the mariner element from Drosophila mauritiana in zebrafish
PNAS, April 28, 1998; 95(9): 5182 - 5186.
[Abstract] [Full Text] [PDF]


Home page
Proc. Natl. Acad. Sci. USAHome page
A. R. Lohe, D. De Aguiar, and D. L. Hartl
Mutations in the mariner transposase: The D,D(35)E consensus sequence is nonfunctional
PNAS, February 18, 1997; 94(4): 1293 - 1297.
[Abstract] [Full Text] [PDF]