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Drosophila p53 has been found to be a structural and functional homolog of the tumor suppressor p53. A Drosophila homolog of p53 has been identified. A function contributing to apoptosis has been found for p53. Drosophila is an good model system in which to find out about p53 apoptotic pathways brought on by DNA damage.

Objective: To determine the effect of the genetic counselor on the acceptance of genetic amniocentesis., Methods: We studied women with singleton pregnancies who would be at least 35 years of age at the estimated date of delivery without fetal structural anomalies or family history of chromosomal abnormalities. The acceptance rate of genetic amniocentesis among women evaluated by each counselor was compared with the average acceptance rate for our population. Chi-square test, Fisher exact test and ANOVA were used for analysis., Results: Of the 2,180 women met our inclusion criteria, 1,719 (78.9%) accepted genetic amniocentesis. The maternal age at estimated date of delivery, the proportion of women who conceived by in vitro fertilization, and the proportion with history of miscarriage were similar among women evaluated by each of the six genetic counselors. However, the acceptance rate of genetic amniocentesis was significantly lower in women evaluated by counselor C [115/170 (67.6%), P=0.001] and significantly higher in the group evaluated by counselor D [138/154 (89.6%), P=0.002] compared with the overall study population rate [1719/2180 (78.9%)]. The acceptance rate of 80.4% (210/261, P=0.52), 75.6 % (232/307, P=0.23), 80.9% (443/547, P=0.30] and 78.4% (581/741, P=0.83) for Counselors A, B, E and F respectively did not differ from the overall study population rate., Conclusions: Considerable variation exists in the acceptance rate of genetic amniocentesis among women based on the genetic counselor.

With the availability of complete genome sequence for Drosophila melanogaster, one of the next strategic goals for fly researchers is a complete gene knockout collection. The P-element transposon, the workhorse of D. melanogaster molecular genetics, has a pronounced nonrandom insertion spectrum. It has been estimated that 87% saturation of the approximately 13,500-gene complement of D. melanogaster might require generating and analyzing up to 150,000 insertions. We describe specific improvements to the lepidopteran transposon piggyBac and the P element that enabled us to tag and disrupt genes in D. melanogaster more efficiently. We generated over 29,000 inserts resulting in 53% gene saturation and a more diverse collection of phenotypically stronger insertional alleles. We found that piggyBac has distinct global and local gene-tagging behavior from that of P elements. Notably, piggyBac excisions from the germ line are nearly always precise, piggyBac does not share chromosomal hotspots associated with P and piggyBac is more effective at gene disruption because it lacks the P bias for insertion in 5' regulatory sequences.

Objectives: To determine the effect of in vitro fertilization (IVF), multiple gestation, and history of unkaryotyped miscarriage on the acceptance of genetic amniocentesis., Methods: We studied women expected to be at least 35 years of age at the estimated date of delivery without family history of chromosomal abnormalities or fetal structural anomalies. The influence of IVF, multiple gestation, and history of miscarriage on the acceptance rate of genetic amniocentesis was evaluated. Chi-square test and logistic regression were used for analysis., Results: In singleton pregnancies, the acceptance rate of genetic amniocentesis was 70.7% (58/82) in the IVF group compared to 77.9% (1837/2356) (P = 0.14) in the women who conceived spontaneously. The corresponding values in multiple gestation pregnancies were 71.1% (37/52) and 62.9% (34/54) respectively (P = 0.41). There was no difference in the acceptance rate of amniocentesis between singletons (70.7%) and multiple gestations (71.1%) after IVF (P = 0.96), while in women who conceived spontaneously, the acceptance rate of 78% in singletons was significantly higher than the acceptance rate of 63% in multiple gestations (P = 0.008). Adjusting for confounding variables, women with multiple gestations were about 40% less likely to accept genetic amniocentesis (OR = 0.63, 95% CI = 0.39-1.00, P = 0.05), while women with a history of miscarriage were about 17% less likely to accept genetic amniocentesis (OR = 0.83, 95% CI = 0.68-1.00, P = 0.05). Adjusting for multiple gestation and previous miscarriage, IVF was not independently associated with acceptance of genetic amniocentesis (OR = 0.84, 95% CI = 0.54-1.29, P = 0.42)., Conclusions: There is no difference in the acceptance rate of genetic amniocentesis among women with IVF pregnancies compared with those who conceive spontaneously, after adjusting for multiple gestation and previous miscarriage. Unlike women who conceive spontaneously, the decision to accept amniocentesis appears not to be influenced by the presence of multiple gestation in women with IVF pregnancies., (Copyright 2003 John Wiley & Sons, Ltd.)

Moesin, ezrin, and radixin (MER) are components of the cortical actin cytoskeleton and membrane processes such as filopodia and microvilli. Their C-terminal tails contain an extended region that is predicted to be helical, an actin binding domain, and a region(s) that participates in self-association. We engineered an in vivo fluorescent actin binding protein (GFP-moe) by joining sequences that encode the jellyfish green fluorescent protein (GFP) to sequences that encode the C-terminal end of the sole Drosophila MER homolog, moesin [Moesin-like gene product, referred to previously as the D17 MER-like protein; Edwards et al., 1994, Proc. Natl. Acad. Sci. USA 91, 4589], and Dmoesin [McCartney and Fehon, 1996, J. Cell Biol. 133, 843]. Transgenic flies expressing this fusion protein under control of the hsp70 promoter were generated and used for analysis of cell shape changes during morphogenesis of various developmental stages and tissues. Following heat shock, high levels of stable fusion protein are produced by all somatic tissues. GFP-moe localizes to the cortical actin cytoskeleton, providing a strong in vivo marker for cell shape and pattern during epithelial morphogenesis. The protein also becomes highly enriched in pseudopods, microvilli, axons, denticles, the border cell process, and other membrane projections, potentially by binding to endogenous moesin as well as actin. We show that GFP-moe can be used to examine the development and behavior of these dynamic structures in live specimens. We observe a bright green fluorescent, presumably actin-rich, polar cell proboscis that inserts itself into the forming micropyle and appears to maintain an opening for sperm passage around which the chorion is formed. We also confirm the existence of an actin-rich purse string at the leading edge of the lateral epidermis and provide a dynamic analysis of its behavior as it migrates during dorsal closure. Observations of embryos, larvae, and pupae show that GFP-moe is also useful for labeling the developing nervous system and will be a good general marker of dynamic cell behavior during morphogenesis in live tissues and demonstrate that fusion of a subcellular localization signal to GFP greatly increases its utility as a cell marker., (Copyright 1997 Academic Press.)