Mariana Wolfner | |
---|---|
Born | Mariana Federica Wolfner |
Alma mater | Cornell University (BS) Stanford University (PhD) |
Awards | Member of the National Academy of Sciences (2019) Genetics Society of America Medal (2018) |
Scientific career | |
Fields | Reproductive biology Drosophila genetics Early embryogenesis Seminal proteins [1] |
Institutions | Cornell University University of California, San Diego |
Thesis | Ecdysone-responsive genes of the salivary gland of Drosophila melanogaster (1980) |
Doctoral advisor | David Hogness |
Website | mbg |
Mariana Federica Wolfner is the Goldwin Smith Professor of molecular biology and genetics at Cornell University. Her research investigates sexual conflict in the fruit fly Drosophila melanogaster . [1] She was elected a member of the National Academy of Sciences (NAS) in 2019 in recognition of her distinguished and continuing achievements in original research. [2] [3]
Wolfner became interested in biology as a child. She decided to study at Cornell University because it was well known for genetics. [4] During her undergraduate degree she worked in Gerald Fink's laboratory, studying the control of amino acids in yeast, and graduated in 1974. [4] [5] She moved to Stanford University for her graduate degree, where she was a doctoral student in the lab of David Hogness. [6] She was one of the first to use recombinant DNA to isolate the genes in Drosophila . Wolfner pioneered the use of cDNA hybridisation to isolate the genes which respond to ecdysone during metamorphosis. [4]
Wolfner joined University of California, San Diego for a postdoctoral fellowship under the supervision of Bruce Baker. [4] Here she started to study the genes that are involved in sex determination of Drosophila. With Baker, Wolfner cloned the doublesex gene. [4]
Wolfner joined the faculty at Cornell University in 1983. [7] She has explored the mechanisms that are responsible for sex determination and development in Drosophila. [4] Wolfner has identified over two hundred of the drosophila seminal fluid proteins and their influence on physiology and behaviour. [8] She performed genetic ablation to identify the genes that encoded seminal fluid proteins. [4] She found that female drosophila store semen for a while before fertilisation, and become less interested in males after mating. [9] Wolfner found that during mating the seminal fluid proteins that were created in male accessory glands were transferred to females, and caused postmating changes. [10] [11] She spent two years at the University of California, San Diego working on mutant phenotypes in seminal fluid proteins. [12]
In her extensive studies of the seminal fluid proteins of Drosophila, [1] Wolfner has uncovered new information about sexual conflict. [4] She showed that seminal fluid proteins that increase the egg-laying rate of females are beneficial for males, but can reduce the lifespan of the female drosophila. [4] [13] Apc26Aa is one of the seminal fluid proteins that can cause these postmating changes in female drosophila. [9] She found that seminal fluid proteins can act as switches that activate physiology in the mated females. [14] [15] [16] Wolfner works with Laura Harrington on the identification of seminal fluid proteins in mosquitoes that are responsible for the transmission of the Zika and dengue viruses. [4] [17]
She also works on the egg-to-embryo transition, after the oocyte is released and before it is activated to begin embryogenesis. [17] Wolfner demonstrated that the egg-to-embryo transition is not the same in drosophila and mammals. [4] In drosophila, the oocyte is squeezed into the oviduct, whereas in mammals the sperm triggers the transition. She showed that the activation process in drosophila involves a spike of calcium, which triggers downstream pathways. [4]
She was appointed the Goldwin Smith Professor of Molecular Biology & Genetics in Cornell University in 2013.[ citation needed ]
Drosophila is a genus of fly, belonging to the family Drosophilidae, whose members are often called "small fruit flies" or pomace flies, vinegar flies, or wine flies, a reference to the characteristic of many species to linger around overripe or rotting fruit. They should not be confused with the Tephritidae, a related family, which are also called fruit flies ; tephritids feed primarily on unripe or ripe fruit, with many species being regarded as destructive agricultural pests, especially the Mediterranean fruit fly.
Drosophila melanogaster is a species of fly in the family Drosophilidae. The species is often referred to as the fruit fly or lesser fruit fly, or less commonly the "vinegar fly", "pomace fly", or "banana fly". In the wild, D. melanogaster are attracted to rotting fruit and fermenting beverages, and are often found in orchards, kitchens and pubs.
Sperm competition is the competitive process between spermatozoa of two or more different males to fertilize the same egg during sexual reproduction. Competition can occur when females have multiple potential mating partners. Greater choice and variety of mates increases a female's chance to produce more viable offspring. However, multiple mates for a female means each individual male has decreased chances of producing offspring. Sperm competition is an evolutionary pressure on males, and has led to the development of adaptations to increase male's chance of reproductive success. Sperm competition results in a sexual conflict between males and females. Males have evolved several defensive tactics including: mate-guarding, mating plugs, and releasing toxic seminal substances to reduce female re-mating tendencies to cope with sperm competition. Offensive tactics of sperm competition involve direct interference by one male on the reproductive success of another male, for instance by mate guarding or by physically removing another male's sperm prior to mating with a female. For an example, see Gryllus bimaculatus.
Eric Francis Wieschaus is an American evolutionary developmental biologist and 1995 Nobel Prize-winner.
Octopamine (OA), also known as para-octopamine and norsynephrine among synonyms, is an organic chemical closely related to norepinephrine, and synthesized biologically by a homologous pathway. Octopamine is often considered the major "fight-or-flight" neurohormone of invertebrates. Its name is derived from the fact that it was first identified in the salivary glands of the octopus.
Sexual conflict or sexual antagonism occurs when the two sexes have conflicting optimal fitness strategies concerning reproduction, particularly over the mode and frequency of mating, potentially leading to an evolutionary arms race between males and females. In one example, males may benefit from multiple matings, while multiple matings may harm or endanger females due to the anatomical differences of that species. Sexual conflict underlies the evolutionary distinction between male and female.
Odorant-binding proteins (OBPs) are small soluble proteins secreted by auxiliary cells surrounding olfactory receptor neurons, including the nasal mucus of many vertebrate species and in the sensillar lymph of chemosensory sensilla of insects. OBPs are characterized by a specific protein domain that comprises six α-helices joined by three disulfide bonds. Although the function of the OBPs as a whole is not well established, it is believed that they act as odorant transporters, delivering the odorant molecules to olfactory receptors in the cell membrane of sensory neurons.
Doublesex (dsx) is a gene that is involved in the sex determination system of many insects including the fruit fly Drosophila melanogaster.
Female sperm storage is a biological process and often a type of sexual selection in which sperm cells transferred to a female during mating are temporarily retained within a specific part of the reproductive tract before the oocyte, or egg, is fertilized. This process takes place in some species of animals. The site of storage is variable among different animal taxa and ranges from structures that appear to function solely for sperm retention, such as insect spermatheca and bird sperm storage tubules, to more general regions of the reproductive tract enriched with receptors to which sperm associate before fertilization, such as the caudal portion of the cow oviduct containing sperm-associating annexins. Female sperm storage is an integral stage in the reproductive process for many animals with internal fertilization. It has several documented biological functions including:
Sexual antagonistic co-evolution is the relationship between males and females where sexual morphology changes over time to counteract the opposite's sex traits to achieve the maximum reproductive success. This has been compared to an arms race between sexes. In many cases, male mating behavior is detrimental to the female's fitness. For example, when insects reproduce by means of traumatic insemination, it is very disadvantageous to the female's health. During mating, males will try to inseminate as many females as possible, however, the more times a female's abdomen is punctured, the less likely she is to survive. Females that possess traits to avoid multiple matings will be more likely to survive, resulting in a change in morphology. In males, genitalia is relatively simple and more likely to vary among generations compared to female genitalia. This results in a new trait that females have to avoid in order to survive.
Interlocus sexual conflict is a type of sexual conflict that occurs through the interaction of a set of antagonistic alleles at two or more different loci, or the location of a gene on a chromosome, in males and females, resulting in the deviation of either or both sexes from the fitness optima for the traits. A co-evolutionary arms race is established between the sexes in which either sex evolves a set of antagonistic adaptations that is detrimental to the fitness of the other sex. The potential for reproductive success in one organism is strengthened while the fitness of the opposite sex is weakened. Interlocus sexual conflict can arise due to aspects of male–female interactions such as mating frequency, fertilization, relative parental effort, female remating behavior, and female reproductive rate.
Sarah C.R. Elgin is an American biochemist and geneticist. She is the Viktor Hamburger Professor of biology at Washington University in St. Louis, and is noted for her work in epigenetics, gene regulation, and heterochromatin, and for her contributions to science education.
Drosophila hydei (mosca casera) is a species of Diptera, or the order of flies, in the family Drosophilidae. It is a species in the hydei species subgroup, a group in the repleta species group. Bizarrely, it is also known for having approximately 23 mm long sperm, 10 times the length of the male's body. Drosophila hydei are commonly found on compost piles worldwide, and can be rudimentarily identified by eye owing to their large size and variegated pigment pattern on the thorax. The name derives from Dr R. R. Hyde, who first discovered that the species was distinct from Drosophila repleta. D. hydei are one of the more popular flies used as feeders in the pet trade. A few varieties are available, some flightless. They are very similar to Drosophila melanogaster, despite having separated 50 million years ago.
Cycle (cyc) is a gene in Drosophila melanogaster that encodes the CYCLE protein (CYC). The Cycle gene (cyc) is expressed in a variety of cell types in a circadian manner. It is involved in controlling both the sleep-wake cycle and circadian regulation of gene expression by promoting transcription in a negative feedback mechanism. The cyc gene is located on the left arm of chromosome 3 and codes for a transcription factor containing a basic helix-loop-helix (bHLH) domain and a PAS domain. The 2.17 kb cyc gene is divided into 5 coding exons totaling 1,625 base pairs which code for 413 aminos acid residues. Currently 19 alleles are known for cyc. Orthologs performing the same function in other species include ARNTL and ARNTL2.
Montserrat Aguadé Porres is a professor emeritus of genetics at University of Barcelona and member of the Institut d'Estudis Catalans.
Seminal fluid proteins (SFPs) or accessory gland proteins (Acps) are one of the non-sperm components of semen. In many animals with internal fertilization, males transfer a complex cocktail of proteins in their semen to females during copulation. These seminal fluid proteins often have diverse, potent effects on female post-mating phenotypes. SFPs are produced by the male accessory glands.
De novo gene birth is the process by which new genes evolve from non-coding DNA. De novo genes represent a subset of novel genes, and may be protein-coding or instead act as RNA genes. The processes that govern de novo gene birth are not well understood, although several models exist that describe possible mechanisms by which de novo gene birth may occur.
Drosophila metlerri, commonly known as the Sonoran Desert fly, is a fly in the genus Drosophila. The species is found in North America and is most concentrated along the southern coast of California and in Mexico. D. mettleri are dependent on plant hosts, namely, the saguaro and cardon cacti. Thus, they are most prevalent in arid, desert conditions. It is able to detoxify chemicals found in the rotting liquid of cacti hosts, which allows it to use otherwise lethal soil as a nesting site.
R. Scott Hawley is an American geneticist and investigator at the Stowers Institute for Medical Research in Kansas City, Missouri, a member of the US National Academy of sciences and fellow of the American Association for the Advancement of Science. He has been President of the Genetics Society of America, and leads a research team focused on the molecular mechanisms that regulate chromosome behavior during meiosis.
Christine Merlin is a French chronobiologist and an associate professor of biology at Texas A&M University. Merlin's research focuses on the underlying genetics of the monarch butterfly circadian clock and explores how circadian rhythms modulate monarch behavior and navigation.