scholarly journals Targeting female flight for genetic control of mosquitoes

2020 ◽  
Vol 14 (12) ◽  
pp. e0008876
Author(s):  
David Navarro-Payá ◽  
Ilona Flis ◽  
Michelle A. E. Anderson ◽  
Philippa Hawes ◽  
Ming Li ◽  
...  

Aedes aegypti Act4 is a paralog of the Drosophila melanogaster indirect flight muscle actin gene Act88F. Act88F has been shown to be haploinsufficient for flight in both males and females (amorphic mutants are dominant). Whereas Act88F is expressed in indirect flight muscles of both males and females, expression of Act4 is substantially female-specific. We therefore used CRISPR/Cas9 and homology directed repair to examine the phenotype of Act4 mutants in two Culicine mosquitoes, Aedes aegypti and Culex quinquefasciatus. A screen for dominant female-flightless mutants in Cx. quinquefasciatus identified one such mutant associated with a six base pair deletion in the CxAct4 coding region. A similar screen in Ae. aegypti identified no dominant mutants. Disruption of the AeAct4 gene by homology-dependent insertion of a fluorescent protein marker cassette gave a recessive female-flightless phenotype in Ae. aegypti. Reproducing the six-base deletion from Cx. quinquefasciatus in Ae. aegypti using oligo-directed mutagenesis generated dominant female-flightless mutants and identified additional dominant female-flightless mutants with other in-frame insertions or deletions. Our data indicate that loss of function mutations in the AeAct4 gene are recessive but that short in-frame deletions produce dominant-negative versions of the AeAct4 protein that interfere with flight muscle function. This makes Act4 an interesting candidate for genetic control methods, particularly population-suppression gene drives targeting female viability/fertility.

10.28945/3248 ◽  
2008 ◽  
Author(s):  
Cecille Marsh

Previous research conducted by the author investigated the socio-political backgrounds of two groups of female students studying computer-related university programmes. They came from distinctly different backgrounds and were enrolled at two institutions with very different legacies. The author found that socio-political factors, in particular the role of a dominant female household head and aggressive governmental affirmative action, had a significant effect on the girls’ levels of confidence and subsequently on their decision to study computer-related courses. Based on this insight, the researcher undertook to look further into gender diversity with respect to self-perceived general computer confidence and self-perceived ability to program a computer. A sample of both female and male Information T echnology students from very similar disadvantaged socio-economic backgrounds was surveyed. The sample of 204 students was drawn from all three years of the National Diploma in Information Technology. The author considered the following research questions: (i) Do males and females studying computer-related courses have differing computer selfefficacy levels? (ii) Do males and females studying computer programming have differing attitudes towards their ability to program? (iii) Do males and females differ in their attitudes towards the programming learning environment?


2018 ◽  
Vol 7 (18) ◽  
Author(s):  
Matthew Chung ◽  
Laura Teigen ◽  
Silvia Libro ◽  
Robin E. Bromley ◽  
Nikhil Kumar ◽  
...  

Here, we present a comprehensive transcriptomics data set of Brugia malayi, its Wolbachia endosymbiont wBm, and its vector host. This study samples from 16 stages across the entire B. malayi life cycle, including stage 1 through 4 larvae, adult males and females, embryos, immature microfilariae, and mature microfilariae.


2001 ◽  
Vol 152 (4) ◽  
pp. 753-764 ◽  
Author(s):  
Nguyen Truc Bui ◽  
Antonia Livolsi ◽  
Jean-Francois Peyron ◽  
Jochen H.M. Prehn

NGF has been shown to support neuron survival by activating the transcription factor nuclear factor-κB (NFκB). We investigated the effect of NGF on the expression of Bcl-xL, an anti–apoptotic Bcl-2 family protein. Treatment of rat pheochromocytoma PC12 cells, human neuroblastoma SH-SY5Y cells, or primary rat hippocampal neurons with NGF (0.1–10 ng/ml) increased the expression of bcl-xL mRNA and protein. Reporter gene analysis revealed a significant increase in NFκB activity after treatment with NGF that was associated with increased nuclear translocation of the active NFκB p65 subunit. NGF-induced NFκB activity and Bcl-xL expression were inhibited in cells overexpressing the NFκB inhibitor, IκBα. Unlike tumor necrosis factor-α (TNF-α), however, NGF-induced NFκB activation occurred without significant degradation of IκBs determined by Western blot analysis and time-lapse imaging of neurons expressing green fluorescent protein–tagged IκBα. Moreover, in contrast to TNF-α, NGF failed to phosphorylate IκBα at serine residue 32, but instead caused significant tyrosine phosphorylation. Overexpression of a Y42F mutant of IκBα potently suppressed NFG-, but not TNF-α–induced NFκB activation. Conversely, overexpression of a dominant negative mutant of TNF receptor-associated factor-6 blocked TNF-α–, but not NGF-induced NFκB activation. We conclude that NGF and TNF-α induce different signaling pathways in neurons to activate NFκB and bcl-x gene expression.


2006 ◽  
Vol 80 (20) ◽  
pp. 10055-10063 ◽  
Author(s):  
Adrian Valli ◽  
Ana Montserrat Martín-Hernández ◽  
Juan José López-Moya ◽  
Juan Antonio García

ABSTRACT The P1 protein of viruses of the family Potyviridae is a serine proteinase, which is highly variable in length and sequence, and its role in the virus infection cycle is not clear. One of the proposed activities of P1 is to assist HCPro, the product that viruses of the genus Potyvirus use to counteract antiviral defense mediated by RNA silencing. Indeed, an HCPro-coding region is present in all the genomes of members of the genera Potyvirus, Rymovirus, and Tritimovirus that have been sequenced. However, it was recently reported that a sequence coding for HCPro is lacking in the genome of Cucumber vein yellowing virus (CVYV), a member of the genus Ipomovirus, the fourth monopartite genus of the family. In this study, we provide further evidence that P1 enhances the activity of HCPro in members of the genus Potyvirus and show that it is duplicated in the ipomovirus CVYV. The two CVYV P1 copies are arranged in tandem, and the second copy (P1b) has RNA silencing suppression activity. CVYV P1b suppressed RNA silencing induced either by sense green fluorescent protein (GFP) mRNA or by a GFP inverted repeat RNA, indicating that CVYV P1b acts downstream of the formation of double-stranded RNA. CVYV P1b also suppressed local silencing in agroinfiltrated patches of transgenic Nicotiana benthamiana line 16c and delayed its propagation to the neighboring cells. However, neither the short-distance nor long-distance systemic spread of silencing of the GFP transgene was completely blocked by CVYV P1b. CVYV P1b and P1-HCPro from the potyvirus Plum pox virus showed very similar behaviors in all the assays carried out, suggesting that evolution has found a way to counteract RNA silencing by similar mechanisms using very different proteins in viruses of the same family.


1985 ◽  
Vol 5 (1) ◽  
pp. 17-26
Author(s):  
L Naumovski ◽  
G Chu ◽  
P Berg ◽  
E C Friedberg

We determined the complete nucleotide sequence of the RAD3 gene of Saccharomyces cerevisiae. The coding region of the gene contained 2,334 base pairs that could encode a protein with a calculated molecular weight of 89,796. Analysis of RAD3 mRNA by Northern blots and by S1 nuclease mapping indicated that the transcript was approximately 2.5 kilobases and did not contain intervening sequences. Fusions between the RAD3 gene and the lac'Z gene of Escherichia coli were constructed and used to demonstrate that the RAD3 gene was not inducible by DNA damage caused by UV radiation or 4-nitroquinoline-1-oxide. Two UV-sensitive chromosomal mutant alleles of RAD3, rad3-1 and rad3-2, were rescued by gap repair of a centromeric plasmid, and their sequences were determined. The rad3-1 mutation changed a glutamic acid to lysine, and the rad3-2 mutation changed a glycine to arginine. Previous studies have shown that disruption of the RAD3 gene results in loss of an essential function and is associated with inviability of haploid cells. In the present experiments, plasmids carrying the rad3-1 and rad3-2 mutations were introduced into haploid cells containing a disrupted RAD3 gene. These plasmids expressed the essential function of RAD3 but not its DNA repair function. A 74-base-pair deletion at the 3' end of the RAD3 coding region or a fusion of this deletion to the E. coli lac'Z gene did not affect either function of RAD3.


1999 ◽  
Vol 112 (12) ◽  
pp. 1957-1965 ◽  
Author(s):  
K. Venkateswarlu ◽  
F. Gunn-Moore ◽  
J.M. Tavare ◽  
P.J. Cullen

ADP-ribosylation factors (ARFs) are small GTP-binding proteins that function as regulators of eukaryotic vesicle trafficking. Cytohesin-1 is a member of a family of ARF guanine nucleotide-exchange factors that contain a C-terminal pleckstrin homology (PH) domain which has been proposed to bind the lipid second messenger phosphatidylinositol 3,4,5-trisphosphate (PIP3). Here we demonstrate that in vitro, recombinant cytohesin-1 binds, via its PH domain, the inositol head group of PIP3, inositol 1,3,4, 5-tetrakisphosphate (IP4), with an affinity greater than 200-fold higher than the inositol head group of either phosphatidylinositol 4, 5-bisphosphate or phosphatidylinositol 3,4-bisphosphate. Moreover, addition of glycerol or diacetylglycerol to the 1-phosphate of IP4 does not alter the ability to interact with cytohesin-1, data which is entirely consistent with cytohesin-1 functioning as a putative PIP3 receptor. To address whether cytohesin-1 binds PIP3 in vivo, we have expressed a chimera of green fluorescent protein (GFP) fused to the N terminus of cytohesin-1 in PC12 cells. Using laser scanning confocal microscopy we demonstrate that either EGF- or NGF-stimulation of transiently transfected PC12 cells results in a rapid translocation of GFP-cytohesin-1 from the cytosol to the plasma membrane. This translocation is dependent on the cytohesin-1 PH domain and occurs with a time course that parallels the rate of plasma membrane PIP3 production. Furthermore, the translocation requires the ability of either agonist to activate PI 3-kinase, since it is inhibited by wortmannin (100 nM), LY294002 (50 microM) and by coexpression with a dominant negative p85. This data therefore suggests that in vivo cytohesin-1 can interact with PIP3 via its PH domain.


2001 ◽  
Vol 114 (6) ◽  
pp. 1145-1153 ◽  
Author(s):  
C. Gao ◽  
S. Negash ◽  
H.S. Wang ◽  
D. Ledee ◽  
H. Guo ◽  
...  

The cyclin-dependent kinase member, Cdk5, is expressed in a variety of cell types, but neuron-specific expression of its activator, p35, is thought to limit its activity to neurons. Here we demonstrate that both Cdk5 and p35 are expressed in the human astrocytoma cell line, U373. Cdk5 and p35 are present in the detergent-insoluble cytoskeletal fraction of this cell line and Cdk5 localizes to filopodia and vinculin-rich regions of cell-matrix contact in lamellopodia. When exposed to a 46(o)C heat shock, U373 cells change shape, lose cell-matrix contacts and show increased levels of apoptosis. To test whether Cdk5 activation might play a role in these events, U373 cells were stably transfected with histidine-tagged or green fluorescent protein-tagged constructs of Cdk5 or a dominant negative mutation, Cdk5T33. Under normal growth conditions, growth characteristics of the stably transfected lines were indistinguishable from untransfected U373 cells and Cdk5 localization was not changed. However, when subjected to heat shock, cells stably transfected with Cdk5-T33 remained flattened, showed little loss of cell-matrix adhesion, and exhibited significantly lower levels of apoptosis. In contrast, cells that overexpressed wild-type Cdk5 showed morphological changes similar to those seen in untransfected U373 cells in response to heat shock and had significantly higher levels of apoptosis. Heat-shocked cells showed changes in p35 mobility and stability of the Cdk5/p35 complex consistent with endogenous Cdk5 activity. Together these findings suggest that endogenous Cdk5 activity may play a key role in regulating morphology, attachment, and apoptosis in U373 cells, and raise the possibility that Cdk5 may be a general regulator of cytoskeletal organization and cell adhesion in both neuronal and non-neuronal cells.


2011 ◽  
Vol 192 (3) ◽  
pp. 497-512 ◽  
Author(s):  
Elisabeth D. Coene ◽  
Catarina Gadelha ◽  
Nicholas White ◽  
Ashraf Malhas ◽  
Benjamin Thomas ◽  
...  

BRCA1 C-terminal (BRCT) domains in BRCA1 are essential for tumor suppressor function, though the underlying mechanisms remain unclear. We identified ezrin, radixin, and moesin as BRCA1 BRCT domain–interacting proteins. Ezrin–radixin–moesin (ERM) and F-actin colocalized with BRCA1 at the plasma membrane (PM) of cancer cells, especially at leading edges and focal adhesion sites. In stably expressing cancer cells, high levels of enhanced green fluorescent protein (EGFP)-BRCA11634–1863 acted as a dominant-negative factor, displacing endogenous BRCA1 from the PM. This led to delayed cell spreading, increased spontaneous motility, and irregular monolayer wound healing. MCF-7 cells (intact BRCA1) showed lower motility than HCC1937 cells (truncated BRCA1), but expression of EGFP-BRCA11634–1863 in MCF-7 increased motility. Conversely, full-length BRCA1 expression in HCC1937 decreased motility but only if the protein retained ubiquitin ligase activity. We conclude that full-length BRCA1 is important for complete tumor suppressor activity via interaction of its BRCT domains with ERM at the PM, controlling spreading and motility of cancer cells via ubiquitin ligase activity.


1985 ◽  
Vol 38 (3) ◽  
pp. 275 ◽  
Author(s):  
GG Foster ◽  
WG Vogt ◽  
TL Woodburn

The results of progeny tests of males and females captured during two field trials of sex-linked translocation strains for genetic control of L. cuprina are presented. Males released as mature larvae survived to adulthood and mated with field females. However, the levels of genetic death introduced into the population were insufficient to suppress the native population. This was due partly to seasonal ineffectiveness of the release method, and partly to poor performance of the released males. On average, the mating competitiveness of the released males was only one-third that of field males, whereas their field-reared, translocation-bearing sons were fully competitive with native males.


Sign in / Sign up

Export Citation Format

Share Document