Elizabeth Williams

Generation and Characterization of MacGreen Mice, the Cfs1r -EGFP Transgenic Mice

Macrophage colony-stimulating factor (CSF-1) regulates the differentiation, proliferation, and survival of cells of the mononuclear phagocyte system. The activity of CSF-1 is mediated by the CSF-1 receptor (CSFlR, CD115) that is encoded by c-fms (Csf1r) protooncogene. The c-fms gene is expressed in macrophage, trophoblast cell lineages, and to some extent granulocytes. A reporter gene construct containing 3.5-kb of 5 flanking sequence and the downstream intron 2 of the c-fms gene directed expression of enhanced green fluorescent protein (EGFP) to cells expressing the c-fms gene including the macrophages and trophoblasts. EGFP was detected in trophoblasts from the earliest stage of implantation. During embryonic development, EGFP expression highlighted the large numbers of c-fms positive macrophages in most organs. These embryonic macrophages contribute to organogenesis and tissue remodeling. In adult c-fms EGFP transgenic mice, which have been called the MacGreen mice, EGFP expressed in all tissue macrophage populations and permitted convenient detection of tissue macrophages as well as facilitates their isolation from various tissues.

Improving population estimates of Glossy Black-Cockatoos (Calyptorhynchus lathami) using photo-identification

Abstract Site-based population estimates of the threatened Glossy Black-Cockatoo (‘GBC’; Calyptorhynchus lathami) are often calculated based on age and sex details from transect counts. However, these estimates do not distinguish individual birds, which may result in over-or under-estimation of the population. Two methods were used to estimate GBC populations in Mugii Murum-ban State Conservation Area, New South Wales: (1) the traditional transect method, and (2) a photographic method, which used plumage patterns (primarily the yellow facial feathers of females) and other supporting features to discriminate between foraging GBC family units. The second method has been used previously on Kangaroo Island, South Australia. A catalogue with a matrix of discriminating features was established based on the photographic method; this resulted in a higher population estimate than the transect method in two seasons (winter and spring), as well as providing an annual population estimate, and information on breeding dynamics and local movement of individual family units between foraging habitat. Recommendations for the application of the photographic method are provided. The method provides benefits at both the local scale (with more accurate site population estimates and information on population dynamics) and, with widespread adoption and national cataloguing, valuable knowledge on regional movement patterns and distribution.

Program and Abstracts of the 7th Transgenic Technology Meeting (TT2007)

The Australian beef industry places the greatest value in bulls, in comparison to cows, for prime beef production. Male carcasses can be sold for a larger profit due to their increased muscle mass. This project aims to demonstrate the feasibility of producing male animals that can sire male only offspring, through a transgenic approach in mice that could later be translated into livestock production systems. The mouse Sry (Sex determining region on the Y) gene has been shown to provide the initiating molecular signal leading to male sex determination in mammals. Sry has also been shown to cause sex reversal in XX mice transgenic for the gene. In this project Sry will be targeted to a locus not subject to X-inactivation on the X chromosome of XY mice. These mice will be bred to determine how the transgene is passed on, to determine expression of the transgene, and to assess its activity in causing XX sex reversal. The male mice transgenic for the Sry gene on their X chromosome will be produced using tetraploid aggregation, which in a single step produces 100% ES cell derived embryos. The same target locus can later be used to introduce the bovine SRY gene onto the X chromosome of bovidae species and using germ cell transplantation produce sex reversed animals. This would bypass the need for expensive chimera crosses and provide farmers with a stud bull capable of producing only sons.Program and Abstracts of the 7th Transgenic Technology Meeting (TT2007)

6th Transgenic Technology Meeting report (http://www.cnb.uam.es/ ∼tt2005)

The 6th Transgenic Technology Meeting was held in Barcelona, September 2005. The meeting in Barcelona was one of the largest in TTM series since its inception in Stockholm in 1999. Sessions held included topics on new transgenics technologies; the generation and breeding of transgenics and knockout mice; functional genomics; analysis of genetically modified mice and mouse genetics and development.