Drosophila_melanogaster_-_side_(aka).jpg (546 × 424 pixels, file size: 55 KB, MIME type: image/jpeg)| Drosophila melanogaster | |
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.jpg) Drosophila melanogaster, macho | |
| Clasificación científica | |
| Reino: | Animalia |
| Filo: | Arthropoda |
| Clase: | Insecta |
| Orden: | Diptera |
| Suborden: | Brachycera |
| Familia: | Drosophilidae |
| Subfamilia: | Drosophilinae |
| Género: | Drosophila |
| Subgénero: | Sophophora |
| Complejo específico: | melanogaster complex |
| Especie: | D. melanogaster Meigen, 1830[1 |
Drosophila melanogaster (literalmente "amante del rocío de vientre negro"), también llamada mosca del vinagre o mosca de la fruta, es una especie de díptero braquícero de la familia Drosophilidae. Recibe su nombre debido a que se alimenta de frutas en proceso de fermentación tales como manzanas, bananas, uvas, etc. Es una especie utilizada frecuentemente en experimentación genética, dado que posee un reducido número de cromosomas (4 pares), breve ciclo de vida (15-21 días) y aproximadamente el 61% de los genes de enfermedades humanas que se conocen tienen una contrapartida identificable en el genoma de las moscas de la fruta, y el 50% de las secuencias proteínicas de la mosca tiene análogos en los mamíferos.[2]
Para propósitos de investigación, fácilmente pueden reemplazar a los humanos. Se reproducen rápidamente, de modo que se pueden estudiar muchas generaciones en un corto espacio de tiempo, y ya se conoce el mapa completo de su genoma. Fue adoptada como animal de experimentación genética por Thomas Morgan a principios del siglo XX. Sus 165 Mb de genoma (1 Mb = 1 millón de pares de bases) fueron publicados en marzo de 2000 gracias al consorcio público y la compañía Celera Genomics.[3] Alberga alrededor de 13.600 genes.
WIKIPEDIA. | |
| Las moscas criadas en el espacio tienen menor inmunidad |
Mapa
Las moscas criadas en el espacio tienen menor inmunidad
(EFE)–hace 2 días
Washington, 24 ene (EFEUSA).- Las moscas criadas en un transbordador espacial estadounidense muestran una deficiencia en áreas de su sistema de inmunidad que comparten los humanos y otros mamíferos, según un estudio que difunde hoy Public Library of Science ONE.
Los científicos ya sabían que el vuelo espacial afecta las respuestas de inmunidad, según indicó Deborah Kimbrell, del Departamento de Biología Molecular y Celular en el Colegio de Ciencias Biológicas de la Universidad de California, en Davis, autora principal del estudio.
Las moscas del tipo Drosophila, como las del estudio, comparten muchos aspectos fundamentales del sistema de inmunidad con los mamíferos tales como ratones y humanos.
Con fondos de la agencia espacial estadounidense NASA, Kimbrell y sus colegas iniciaron el primer estudio de la inmunidad de las Drosophilas en ambientes de gravedad aumentada, y luego micro gravedad en el vuelo espacial.
Durante una misión de doce días del transbordador Discovery se enviaron al espacio huevos de moscas que toman unos diez días para desarrollarse hasta ser adultas.
Cuando las moscas retornaron a la Tierra, Kimbrell y sus colegas probaron sus respuestas a dos tipos de infecciones: un hongo -que las moscas combaten mediante una senda de inmunidad mediada por el receptor Toll- y una bacteria que los insectos resisten mediante un gen llamado Imd (por los términos en inglés para deficiencia de inmunidad).
El artículo explicó que tanto Toll como Imd tienen sus equivalentes en los humanos y otros mamíferos.
Si bien la respuesta en las moscas espaciales mediante el gen Imd fue robusta, la senda Toll no funcionó en esos insectos, señalan los autores.
En sus experimentos realizados en el laboratorio terrestre los investigadores encontraron que cuando las moscas fueron sometidas a hipergravedad, en un aparato centrífugo, de hecho su resistencia al hongo mejoró lo cual indica que la senda Toll se fortaleció.
Kimbrell indicó que en el futuro, las naves espaciales diseñadas para misiones de larga duración, podrían incluir aparatos centrífugos que los tripulantes usarían para mantener su masa ósea y muscular, y que también beneficiaría sus sistemas de inmunidad.
© EFE 2014. Está expresamente prohibida la redistribución y la redifusión de todo o parte de los contenidos de los servicios de Efe, sin previo y expreso consentimiento de la Agencia EFE S.A.
DAVIS--You usually see fruit flies hovering over or landing on fermented
fruit—not heading for outer space.
But that’s just what fruit flies studied by genetics researcher and NASA
investigator Deborah Kimbrell of the University of California, Davis will do
when the space shuttle Discovery blasts off on its next mission.
The shuttle, targeted to lift off at the Kennedy Space Center sometime
between July 1 and July 19, will carry a five-man, two-woman crew—and 10
containers of fruit flies and a small container of a fungus.
Her research, the first of its kind, will study the effect of space on the
immune functions of the common fruit fly, Drosophila melanogaster.
Following the 12-day mission, she and her collaborators will infect the fruit
flies with fungus and bacteria to detect their immune responses. Previous
experiments showed that fruit flies can survive in space.
Kimbrell and a contingent of family, friends and fellow scientists will meet
at the Florida space center to cheer the launch. The real work begins after the
shuttle lands. Kimbrell and her collaborators will spend five weeks in a
specially set-up lab at the space center to test the immune functions of the
infected “astronaut” fruit flies, comparing them with infected “ground-based”
fruit flies.
“The findings can be used to determine how space affects the human immune
system,” she said, noting that the human and the fruit fly immune systems are
quite similar. The fruit fly, or “the golden bug,” is a prized tool for genetic
research and developmental studies.
Kimbrell, an associate research geneticist in the Section of Molecular and
Cellular Biology, College of Biological Sciences, specializes in studying fruit
fly genes that control immune responses and how gravity affects them.
Her space research is an extension of her NASA research grant, “Drosophila as
a Model of Immune Function in Conditions of Altered Gravitational Force,”
awarded in 2004.
The fruit flies will be housed in 10 small flat containers during the 12-day
mission, and will be fed once. Kimbrell expects to see many of them survive the
flight, and to yield a second generation within 10 days.
“Only a handful of male and female flies will go up in each container,” she
said. “The big question is how many of their progeny will survive the
spaceflight and return to earth. I hope they stay healthy.”
The fungus on board is Beauveria bassiana , a natural soil-borne
fungus sold commercially as an organic pesticide. It feeds on and destroys an
insect’s internal organs but is not harmful to humans, she said.
Kimbrell’s experiments will center on fruit flies reared on the ground; fruit
flies hatched on Earth and hurdled into space; and flies born reared in space.
She hopes the experiment will answer such questions as:
Kimbrell hypothesizes that the immune systems of spaceflight fruit flies will
not function as well as those of their earthly counterparts. She also speculates
that the spaceflight fungus will be more virulent than typical fungus.
The spaceflight experiment will mesh her two passions, space and fruit flies.
Born at Goodfellow Air Force Base, Texas, she grew up in an Air Force family.
Her father, Billy, a master sergeant who served in Vietnam and Korea, is a space
enthusiast. Her brother, Steve, became an aeronautics engineer. Her husband,
Ingemar Olsson, is a private pilot.
And Drosophila? The red-eyed, black-tipped abdomen insect that’s less than an
eighth of an inch long?
“ I first saw Drosophila through a dissecting microscope when I was a
graduate student,” said Kimbrell, who received her doctorate in genetics at UC
Berkeley after graduating from Mills College, Oakland. “It was love at first
sight.”
Post-doctorate fellowships took her to Cambridge University, England and to
the University of Stockholm, Sweden. At Stockholm, she participated in
pioneering research that led to the establishment of the fruit fly as the common
model for studying the effect on genes, similar to humans, when infected with
different types of bacteria and fungus.
That was in the 1980s. Now a leading scientist in her field, she lectures at
Drosophila conferences in France, Italy and Japan and the United States.
“Drosophila,” she said, “is in an interesting position as a research
organism. Its utility spans from being a model organism for other insects all
the way to humans. Drosophila also is useful in many areas, such as studies on
pesticides and hormonal regulation of development.”
The fruit fly continues to fascinate her. “It has a negative geotaxis
(movement away from the direction of gravity),” she said. “When I turn a flask
of fruit flies upside down, look what happens--the flies swarm from the bottom
to the top.”
Before joining UC Davis in 1999, she served as a senior research fellow at
Rice University, Houston, Texas. “ Houston, we have lift-off!” rings in her
memory.
Meanwhile, the UC Davis scientist is looking forward to the launch and
working with her collaborators, from the NASA Ames Research Center, University
of Central Florida, UC Davis’ Chronic Acceleration Research Unit, Rice
University and the University of Nevada-Las Vegas.
And what do folks think when they learn her fruit flies are going into
space?
“People’s faces light up and after a short pause, they start asking
questions,” she said. “The thought of little fruit flies going up in space
engages people’s imagination and a sense of fun. Drosophila generates scientific
curiosity and amusement.”
Deborah Kimbrell just wishes she could go, too.
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Guillermo Gonzalo Sánchez Achutegui
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