Nixalone is sufficient to convert femaleAedes aegyptiinto fertile males andmyo-sexis needed for male flight

A dominant male-determining locus (M-locus) establishes the male sex (M/m) in the yellow fever mosquito,Aedes aegypti.Nix, a gene in the M-locus, was shown to be a male-determining factor (M factor) as somatic knockout ofNixled to feminized males (M/m) while transient expression ofNixresulted in partially masculinized females (m/m), with male reproductive organs but retained female antennae. It was not clear whether any of the other 29 genes in the 1.3-Mb M-locus are also needed for complete sex-conversion. Here, we report the generation of multiple transgenic lines that expressNixunder the control of its own promoter. Genetic and molecular analyses of these lines provided insights unattainable from previous transient experiments. We show that theNixtransgene alone, in the absence of the M-locus, was sufficient to convert females into males with all male-specific sexually dimorphic features and male-like gene expression. The converted m/m males are flightless, unable to perform the nuptial flight required for mating. However, they were able to father sex-converted progeny when presented with cold-anesthetized wild-type females. We show thatmyo-sex, a myosin heavy-chain gene also in the M-locus, was required for male flight as knockout ofmyo-sexrendered wild-type males flightless. We also show thatNix-mediated female-to-male conversion was 100% penetrant and stable over many generations. Therefore,Nixhas great potential for developing mosquito control strategies to reduce vector populations by female-to-male sex conversion, or to aid in a sterile insect technique that requires releasing only non-biting males.

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Nix confers heritable sex-conversion in Aedes aegypti and myo-sex is needed for male flight

10.1101/595371 ◽

2019 ◽

Cited By ~ 5

Author(s):

Azadeh Aryan ◽

Michelle Anderson ◽

James K. Biedler ◽

Yumin Qi ◽

Justin M. Overcash ◽

...

Keyword(s):

Aedes Aegypti ◽

Mosquito Control ◽

Chain Gene ◽

Wild Type ◽

Myosin Heavy Chain Gene ◽

Protein Coding ◽

Hemizygous Male ◽

Male Sex ◽

Determining Factor ◽

Transmit Disease

A dominant and hemizygous male-determining locus (M locus) establishes the male sex (M/m) in the yellow fever mosquito, Aedes aegypti. Nix is a male-determining factor (M factor) in the M locus and its transient expression in females (m/m) results in partial masculinization. Here, we show that the Nix transgene alone was sufficient to convert females into fertile males, which continued to produce sex-converted progeny in subsequent generations. However, assisted mating with wild-type females was necessary, as the converted m/m males could not fly. Knockout of myo-sex, a myosin heavy chain gene and the only other protein-coding gene reported in the M locus, rendered wild-type males flightless. Thus, Nix alone converts female Ae. aegypti to fertile males and myo-sex is required for male flight. Only female Ae. aegypti mosquitoes bite and transmit disease-causing viruses. Nix-mediated female-to-male conversion is 100% penetrant and stable over many generations, indicating great potential for mosquito control.

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NANOS2 suppresses the cell cycle by repressing mTORC1 activators in embryonic male germ cells

10.1101/2020.09.23.310912 ◽

2020 ◽

Author(s):

Ryuki Shimada ◽

Hiroko Koike ◽

Takamasa Hirano ◽

Yumiko Saga

Keyword(s):

Cell Cycle ◽

Germ Cell ◽

Germ Cells ◽

Rna Binding ◽

Initial Step ◽

Sexually Dimorphic ◽

Wild Type ◽

Male Germ Cells ◽

Cycle Arrest ◽

Male Specific

AbstractDuring murine germ cell development, male germ cells enter the mitotically arrested G0 stage, which is an initial step of sexually dimorphic differentiation. The male specific RNA-binding protein NANOS2 has a key role in suppressing the cell cycle in germ cells. However, the detailed mechanism of how NANOS2 regulates the cell cycle remains unclear. Using single-cell RNA sequencing (scRNA-seq), we extracted the cell cycle state of each germ cell in wild-type and Nanos2-KO testes, and revealed that Nanos2 expression starts in mitotic cells and induces mitotic arrest. We also found that NANOS2 and p38 MAPK work in parallel to regulate the cell cycle, suggesting that several different cascades are involved in the induction of cell cycle arrest. Furthermore, we identified Rheb, a regulator of mTORC1, and Ptma as possible targets of NANOS2. We propose that the repression of the cell cycle is a primary function of NANOS2 and that it is mediated via the suppression of mTORC1 activity by repressing Rheb in a post-transcriptional manner.

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Conservation and diversity in expression of candidate genes regulating socially-induced female-male sex change in wrasses

PeerJ ◽

10.7717/peerj.7032 ◽

2019 ◽

Vol 7 ◽

pp. e7032 ◽

Cited By ~ 2

Author(s):

Jodi T. Thomas ◽

Erica V. Todd ◽

Simon Muncaster ◽

P Mark Lokman ◽

Erin L. Damsteegt ◽

...

Keyword(s):

Expression Patterns ◽

Sex Change ◽

Dominant Male ◽

Neural Pathways ◽

Thalassoma Bifasciatum ◽

Molecular Machinery ◽

Genetic Level ◽

Male Sex ◽

Bluehead Wrasse ◽

Male Specific

Fishes exhibit remarkably diverse, and plastic, patterns of sexual development, most striking of which is sequential hermaphroditism, where individuals readily reverse sex in adulthood. How this stunning example of phenotypic plasticity is controlled at a genetic level remains poorly understood. Several genes have been implicated in regulating sex change, yet the degree to which a conserved genetic machinery orchestrates this process has not yet been addressed. Using captive and in-the-field social manipulations to initiate sex change, combined with a comparative qPCR approach, we compared expression patterns of four candidate regulatory genes among three species of wrasses (Labridae)—a large and diverse teleost family where female-to-male sex change is pervasive, socially-cued, and likely ancestral. Expression in brain and gonadal tissues were compared among the iconic tropical bluehead wrasse (Thalassoma bifasciatum) and the temperate spotty (Notolabrus celidotus) and kyusen (Parajulus poecilepterus) wrasses. In all three species, gonadal sex change was preceded by downregulation of cyp19a1a (encoding gonadal aromatase that converts androgens to oestrogens) and accompanied by upregulation of amh (encoding anti-müllerian hormone that primarily regulates male germ cell development), and these genes may act concurrently to orchestrate ovary-testis transformation. In the brain, our data argue against a role for brain aromatase (cyp19a1b) in initiating behavioural sex change, as its expression trailed behavioural changes. However, we find that isotocin (it, that regulates teleost socio-sexual behaviours) expression correlated with dominant male-specific behaviours in the bluehead wrasse, suggesting it upregulation mediates the rapid behavioural sex change characteristic of blueheads and other tropical wrasses. However, it expression was not sex-biased in temperate spotty and kyusen wrasses, where sex change is more protracted and social groups may be less tightly-structured. Together, these findings suggest that while key components of the molecular machinery controlling gonadal sex change are phylogenetically conserved among wrasses, neural pathways governing behavioural sex change may be more variable.

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Differentiation of a male-specific muscle in Drosophila melanogaster does not require the sex-determining genes doublesex or intersex.

Genetics ◽

10.1093/genetics/132.1.179 ◽

1992 ◽

Vol 132 (1) ◽

pp. 179-191

Author(s):

B J Taylor

Keyword(s):

Drosophila Melanogaster ◽

Abdominal Segment ◽

Specific Form ◽

Null Alleles ◽

Abdominal Muscles ◽

Sexually Dimorphic ◽

Wild Type ◽

Specific Muscle ◽

Sex Lethal ◽

Male Specific

Abstract A pair of muscles span the fifth abdominal segment of male but not female Drosophila melanogaster adults. To establish whether genes involved in the development of other sexually dimorphic tissues controlled the differentiation of sex-specific muscles, flies mutant for five known sex-determining genes were examined for the occurrence of male-specific abdominal muscles. Female flies mutant for alleles of Sex-lethal, defective in sex determination, or null alleles of transformer or transformer-2 are converted into phenotypic males that formed male-specific abdominal muscles. Both male and female flies, when mutant for null alleles of doublesex, develop as nearly identical intersexes in other somatic characteristics. Male doublesex flies produced the male-specific muscles, whereas female doublesex flies lacked them. Female flies, even when they inappropriately expressed the male-specific form of doublesex mRNA, failed to produce the male-specific muscles. Therefore, the wild-type products of the genes Sex-lethal, transformer and transformer-2 act to prevent the differentiation of male-specific muscles in female flies. However, there is no role for the genes doublesex or intersex in either the generation of the male-specific muscles in males or their suppression in females.

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Inhibition of Asaia in Adult Mosquitoes Causes Male-Specific Mortality and Diverse Transcriptome Changes

Pathogens ◽

10.3390/pathogens9050380 ◽

2020 ◽

Vol 9 (5) ◽

pp. 380 ◽

Cited By ~ 1

Author(s):

Maria Vittoria Mancini ◽

Claudia Damiani ◽

Sarah M. Short ◽

Alessia Cappelli ◽

Ulisse Ulissi ◽

...

Keyword(s):

Mosquito Control ◽

Control Strategies ◽

Mosquito Species ◽

Acetic Acid Bacteria ◽

Adult Mosquito ◽

Great Expectations ◽

Innovative Tool ◽

Male Specific

Mosquitoes can transmit many infectious diseases, such as malaria, dengue, Zika, yellow fever, and lymphatic filariasis. Current mosquito control strategies are failing to reduce the severity of outbreaks that still cause high human morbidity and mortality worldwide. Great expectations have been placed on genetic control methods. Among other methods, genetic modification of the bacteria colonizing different mosquito species and expressing anti-pathogen molecules may represent an innovative tool to combat mosquito-borne diseases. Nevertheless, this emerging approach, known as paratransgenesis, requires a detailed understanding of the mosquito microbiota and an accurate characterization of selected bacteria candidates. The acetic acid bacteria Asaia is a promising candidate for paratransgenic approaches. We have previously reported that Asaia symbionts play a beneficial role in the normal development of Anopheles mosquito larvae, but no study has yet investigated the role(s) of Asaia in adult mosquito biology. Here we report evidence on how treatment with a highly specific anti-Asaia monoclonal antibody impacts the survival and physiology of adult Anopheles stephensi mosquitoes. Our findings offer useful insight on the role of Asaia in several physiological systems of adult mosquitoes, where the influence differs between males and females.

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Conservation and diversity in expression of candidate genes regulating socially-induced female-male sex change in wrasses

10.7287/peerj.preprints.27461v1 ◽

2019 ◽

Author(s):

Jodi T Thomas ◽

Erica V Todd ◽

Simon Muncaster ◽

P Mark Lokman ◽

Erin L Damsteegt ◽

...

Keyword(s):

Expression Patterns ◽

Sex Change ◽

Dominant Male ◽

Neural Pathways ◽

Thalassoma Bifasciatum ◽

Molecular Machinery ◽

Genetic Level ◽

Male Sex ◽

Bluehead Wrasse ◽

Male Specific

Fishes exhibit remarkably diverse, and plastic, patterns of sexual development, most striking of which is sequential hermaphroditism, where individuals readily reverse sex in adulthood. How this stunning example of phenotypic plasticity is controlled at a genetic level remains poorly understood. Several genes have been implicated in regulating sex change, yet the degree to which a conserved genetic machinery orchestrates this process has not yet been addressed. Using captive and in-the-field social manipulations to initiate sex change, combined with a comparative qPCR approach, we compared expression patterns of four candidate regulatory genes among three species of wrasses (Labridae) - a large and diverse teleost family where female-to-male sex change is pervasive, socially-cued, and likely ancestral. Expression in brain and gonadal tissues were compared among the iconic tropical bluehead wrasse (Thalassoma bifasciatum) and the temperate spotty (Notolabrus celidotus) and kyusen (Parajulus poecilepterus) wrasses. In all three species, cyp19a1a (encoding gonadal aromatase that converts androgens to oestrogens) and amh (encoding anti-müllerian hormone that primarily regulates male germ cell development) were downregulated and upregulated, respectively, at the initiation of gonadal sex change, and may act concurrently to orchestrate ovary-testis transformation. In the brain, our data argue against a role for brain aromatase (cyp19a1b) in initiating behavioural sex change, as its expression trailed behavioural changes. However, we find that isotocin (it, that regulates teleost socio-sexual behaviours) expression correlated with dominant male-specific behaviours in the bluehead wrasse, suggesting it upregulation mediates the rapid behavioural sex change characteristic of blueheads and other tropical wrasses. However, it expression was not sex-biased in temperate spotty and kyusen wrasses, where sex change is more protracted and social groups may be less tightly-structured. Together, these findings suggest that while key components of the molecular machinery controlling gonadal sex change are phylogenetically conserved among wrasses, neural pathways governing behavioural sex change may be more variable.

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Conservation and diversity in expression of candidate genes regulating socially-induced female-male sex change in wrasses

10.7287/peerj.preprints.27461 ◽

2019 ◽

Author(s):

Jodi T Thomas ◽

Erica V Todd ◽

Simon Muncaster ◽

P Mark Lokman ◽

Erin L Damsteegt ◽

...

Keyword(s):

Expression Patterns ◽

Sex Change ◽

Dominant Male ◽

Neural Pathways ◽

Thalassoma Bifasciatum ◽

Molecular Machinery ◽

Genetic Level ◽

Male Sex ◽

Bluehead Wrasse ◽

Male Specific

Fishes exhibit remarkably diverse, and plastic, patterns of sexual development, most striking of which is sequential hermaphroditism, where individuals readily reverse sex in adulthood. How this stunning example of phenotypic plasticity is controlled at a genetic level remains poorly understood. Several genes have been implicated in regulating sex change, yet the degree to which a conserved genetic machinery orchestrates this process has not yet been addressed. Using captive and in-the-field social manipulations to initiate sex change, combined with a comparative qPCR approach, we compared expression patterns of four candidate regulatory genes among three species of wrasses (Labridae) - a large and diverse teleost family where female-to-male sex change is pervasive, socially-cued, and likely ancestral. Expression in brain and gonadal tissues were compared among the iconic tropical bluehead wrasse (Thalassoma bifasciatum) and the temperate spotty (Notolabrus celidotus) and kyusen (Parajulus poecilepterus) wrasses. In all three species, cyp19a1a (encoding gonadal aromatase that converts androgens to oestrogens) and amh (encoding anti-müllerian hormone that primarily regulates male germ cell development) were downregulated and upregulated, respectively, at the initiation of gonadal sex change, and may act concurrently to orchestrate ovary-testis transformation. In the brain, our data argue against a role for brain aromatase (cyp19a1b) in initiating behavioural sex change, as its expression trailed behavioural changes. However, we find that isotocin (it, that regulates teleost socio-sexual behaviours) expression correlated with dominant male-specific behaviours in the bluehead wrasse, suggesting it upregulation mediates the rapid behavioural sex change characteristic of blueheads and other tropical wrasses. However, it expression was not sex-biased in temperate spotty and kyusen wrasses, where sex change is more protracted and social groups may be less tightly-structured. Together, these findings suggest that while key components of the molecular machinery controlling gonadal sex change are phylogenetically conserved among wrasses, neural pathways governing behavioural sex change may be more variable.

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Identification of octopaminergic neurons that modulate sleep suppression by male sex drive

eLife ◽

10.7554/elife.23130 ◽

2017 ◽

Vol 6 ◽

Cited By ~ 29

Author(s):

Daniel R Machado ◽

Dinis JS Afonso ◽

Alexandra R Kenny ◽

Arzu Öztürk-Çolak ◽

Emilia H Moscato ◽

...

Keyword(s):

Transcription Factor ◽

Calcium Imaging ◽

Normal Male ◽

Sexually Dimorphic ◽

Sex Drive ◽

Sleep Drive ◽

Male Sex ◽

Female Presence ◽

Male Specific ◽

Homeostatic Mechanisms

Molecular and circuit mechanisms for balancing competing drives are not well understood. While circadian and homeostatic mechanisms generally ensure sufficient sleep at night, other pressing needs can overcome sleep drive. Here, we demonstrate that the balance between sleep and sex drives determines whether male flies sleep or court, and identify a subset of octopaminergic neurons (MS1) that regulate sleep specifically in males. When MS1 neurons are activated, isolated males sleep less, and when MS1 neurons are silenced, the normal male sleep suppression in female presence is attenuated and mating behavior is impaired. MS1 neurons do not express the sexually dimorphic FRUITLESS (FRU) transcription factor, but form male-specific contacts with FRU-expressing neurons; calcium imaging experiments reveal bidirectional functional connectivity between MS1 and FRU neurons. We propose octopaminergic MS1 neurons interact with the FRU network to mediate sleep suppression by male sex drive.

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Overexpression of vesicle-associated membrane protein PttVAP27-17 as a tool to improve biomass production and the overall saccharification yields in Populus trees

Biotechnology for Biofuels ◽

10.1186/s13068-021-01895-0 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Madhavi Latha Gandla ◽

Niklas Mähler ◽

Sacha Escamez ◽

Tomas Skotare ◽

Ogonna Obudulu ◽

...

Keyword(s):

Membrane Protein ◽

Biomass Production ◽

Enzymatic Saccharification ◽

Dry Weight ◽

Populus Tremula ◽

Transgenic Trees ◽

Wild Type ◽

Glucose Yield ◽

Transgenic Lines ◽

Wild Type Control

Abstract Background Bioconversion of wood into bioproducts and biofuels is hindered by the recalcitrance of woody raw material to bioprocesses such as enzymatic saccharification. Targeted modification of the chemical composition of the feedstock can improve saccharification but this gain is often abrogated by concomitant reduction in tree growth. Results In this study, we report on transgenic hybrid aspen (Populus tremula × tremuloides) lines that showed potential to increase biomass production both in the greenhouse and after 5 years of growth in the field. The transgenic lines carried an overexpression construct for Populus tremula × tremuloides vesicle-associated membrane protein (VAMP)-associated protein PttVAP27-17 that was selected from a gene-mining program for novel regulators of wood formation. Analytical-scale enzymatic saccharification without any pretreatment revealed for all greenhouse-grown transgenic lines, compared to the wild type, a 20–44% increase in the glucose yield per dry weight after enzymatic saccharification, even though it was statistically significant only for one line. The glucose yield after enzymatic saccharification with a prior hydrothermal pretreatment step with sulfuric acid was not increased in the greenhouse-grown transgenic trees on a dry-weight basis, but increased by 26–50% when calculated on a whole biomass basis in comparison to the wild-type control. Tendencies to increased glucose yields by up to 24% were present on a whole tree biomass basis after acidic pretreatment and enzymatic saccharification also in the transgenic trees grown for 5 years on the field when compared to the wild-type control. Conclusions The results demonstrate the usefulness of gene-mining programs to identify novel genes with the potential to improve biofuel production in tree biotechnology programs. Furthermore, multi-omic analyses, including transcriptomic, proteomic and metabolomic analyses, performed here provide a toolbox for future studies on the function of VAP27 proteins in plants.

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Mosquito Control Priorities in Florida—Survey Results from Florida Mosquito Control Districts

Pathogens ◽

10.3390/pathogens10080947 ◽

2021 ◽

Vol 10 (8) ◽

pp. 947

Author(s):

Rishi Kondapaneni ◽

Ashley N. Malcolm ◽

Brian M. Vazquez ◽

Eric Zeng ◽

Tse-Yu Chen ◽

...

Keyword(s):

State Government ◽

Mosquito Control ◽

Control Strategies ◽

Mosquito Species ◽

Research Priorities ◽

Current Control ◽

Control Programs ◽

Common Control ◽

Surveillance Programs ◽

Research Questions

Florida lies within a subtropical region where the climate allows diverse mosquito species including invasive species to thrive year-round. As of 2021, there are currently 66 state-approved Florida Mosquito Control Districts, which are major stakeholders for Florida public universities engaged in mosquito research. Florida is one of the few states with extensive organized mosquito control programs. The Florida State Government and Florida Mosquito Control Districts have long histories of collaboration with research institutions. During fall 2020, we carried out a survey to collect baseline data on the current control priorities from Florida Mosquito Control Districts relating to (1) priority control species, (2) common adult and larval control methods, and (3) major research questions to address that will improve their control and surveillance programs. The survey data showed that a total of 17 distinct mosquito species were considered to be priority control targets, with many of these species being understudied. The most common control approaches included truck-mounted ultra-low-volume adulticiding and biopesticide-based larviciding. The districts held interest in diverse research questions, with many prioritizing studies on basic science questions to help develop evidence-based control strategies. Our data highlight the fact that mosquito control approaches and priorities differ greatly between districts and provide an important point of comparison for other regions investing in mosquito control, particularly those with similar ecological settings, and great diversity of potential mosquito vectors, such as in Florida. Our findings highlight a need for greater alignment of research priorities between mosquito control and mosquito research. In particular, we note a need to prioritize filling knowledge gaps relating to understudied mosquito species that have been implicated in arbovirus transmission.

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