Allan C. Spradling

Last updated
Allan C. Spradling
Born1949 (age 7475)
Alma mater University of Chicago, Massachusetts Institute of Technology
Awards Newcomb Cleveland Prize (1983)
Genetics Society of America Medal (1989)
Edwin Grant Conklin Medal (2003)
George W. Beadle Award (2003) [1]
Gruber Prize in Genetics (2008)
March of Dimes Prize in Developmental Biology (2018)
Wiley Prize (2024)
Scientific career
Fields Genetics
Institutions Carnegie Institution for Science, Howard Hughes Medical Institute

Allan C. Spradling is an American scientist and principal investigator at the Carnegie Institution for Science and the Howard Hughes Medical Institute who studies egg development in the model organism, Drosophila melanogaster , a fruit fly. [2] He is considered a leading researcher in the developmental genetics of the fruit fly egg and has developed a number of techniques in his career that have led to greater understanding of fruit fly genetics including contributions to sequencing its genome. [2] He is also an adjunct professor at Johns Hopkins University and at the Johns Hopkins University School of Medicine. [2]

Contents

Education

Spradling obtained an A.B. in physics from the University of Chicago and a Ph.D. in cell biology from the Massachusetts Institute of Technology. [2]

Career

Spradling and fellow American geneticist Gerald M. Rubin are considered pioneers in the field of genetics for their work in the early 1980s with their idea to "attach" a gene to a Drosophila transposon, P elements, [3] known to insert itself into fruit fly's chromosomes. [4] From this research came work from other scientists on transposons as a tool for genetic alterations in organisms. [4] [5] [6] [7]

In 2003 Spradling was awarded the Beadle Medal [1] and in 2008 Spradling was awarded the Gruber Prize in Genetics for his work on the Drosophila genome and continues his work in investigating novel technological approaches to genetics, egg development and stem cells. He was elected to the American Philosophical Society in 2016. [8] In 2024 he received the Wiley Prize. [9]

Related Research Articles

<i>Drosophila</i> Genus of flies

Drosophila is a genus of flies, 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.

<span class="mw-page-title-main">Transposable element</span> Semiparasitic DNA sequence

A transposable element is a nucleic acid sequence in DNA that can change its position within a genome, sometimes creating or reversing mutations and altering the cell's genetic identity and genome size. Transposition often results in duplication of the same genetic material. In the human genome, L1 and Alu elements are two examples. Barbara McClintock's discovery of them earned her a Nobel Prize in 1983. Its importance in personalized medicine is becoming increasingly relevant, as well as gaining more attention in data analytics given the difficulty of analysis in very high dimensional spaces.

Selfish genetic elements are genetic segments that can enhance their own transmission at the expense of other genes in the genome, even if this has no positive or a net negative effect on organismal fitness. Genomes have traditionally been viewed as cohesive units, with genes acting together to improve the fitness of the organism. However, when genes have some control over their own transmission, the rules can change, and so just like all social groups, genomes are vulnerable to selfish behaviour by their parts.

<span class="mw-page-title-main">Barbara McClintock</span> American scientist and cytogeneticist (1902–1992)

Barbara McClintock was an American scientist and cytogeneticist who was awarded the 1983 Nobel Prize in Physiology or Medicine. McClintock received her PhD in botany from Cornell University in 1927. There she started her career as the leader of the development of maize cytogenetics, the focus of her research for the rest of her life. From the late 1920s, McClintock studied chromosomes and how they change during reproduction in maize. She developed the technique for visualizing maize chromosomes and used microscopic analysis to demonstrate many fundamental genetic ideas. One of those ideas was the notion of genetic recombination by crossing-over during meiosis—a mechanism by which chromosomes exchange information. She produced the first genetic map for maize, linking regions of the chromosome to physical traits. She demonstrated the role of the telomere and centromere, regions of the chromosome that are important in the conservation of genetic information. She was recognized as among the best in the field, awarded prestigious fellowships, and elected a member of the National Academy of Sciences in 1944.

<i>Drosophila melanogaster</i> Species of 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.

<span class="mw-page-title-main">Mosaic (genetics)</span> Condition in multi-cellular organisms

Mosaicism or genetic mosaicism is a condition in which a multicellular organism possesses more than one genetic line as the result of genetic mutation. This means that various genetic lines resulted from a single fertilized egg. Mosaicism is one of several possible causes of chimerism, wherein a single organism is composed of cells with more than one distinct genotype.

Forward genetics is a molecular genetics approach of determining the genetic basis responsible for a phenotype. Forward genetics provides an unbiased approach because it relies heavily on identifying the genes or genetic factors that cause a particular phenotype or trait of interest.

Alfred Henry Sturtevant was an American geneticist. Sturtevant constructed the first genetic map of a chromosome in 1911. Throughout his career he worked on the organism Drosophila melanogaster with Thomas Hunt Morgan. By watching the development of flies in which the earliest cell division produced two different genomes, he measured the embryonic distance between organs in a unit which is called the sturt in his honor. On February 13, 1968, Sturtevant received the 1967 National Medal of Science from President Lyndon B. Johnson.

<span class="mw-page-title-main">Michael Ashburner</span> English biologist (1942–2023)

Michael Ashburner was an English biologist and Professor in the Department of Genetics at University of Cambridge. He was also the former joint-head and co-founder of the European Bioinformatics Institute (EBI) of the European Molecular Biology Laboratory (EMBL) and a Fellow of Churchill College, Cambridge.

P elements are transposable elements that were discovered in Drosophila as the causative agents of genetic traits called hybrid dysgenesis. The transposon is responsible for the P trait of the P element and it is found only in wild flies. They are also found in many other eukaryotes.

<span class="mw-page-title-main">Mobilome</span>

The mobilome is the entire set of mobile genetic elements in a genome. Mobilomes are found in eukaryotes, prokaryotes, and viruses. The compositions of mobilomes differ among lineages of life, with transposable elements being the major mobile elements in eukaryotes, and plasmids and prophages being the major types in prokaryotes. Virophages contribute to the viral mobilome.

Drosophilist is a term used to refer to both the specific group of scientists trained in the laboratory of Thomas Hunt Morgan, and more generally any scientist who uses the fruit fly Drosophila melanogaster to study genetics, development, neurogenetics, behavior and a host of other subjects in animal biology.

Gerald Mayer Rubin is an American biologist, notable for pioneering the use of transposable P elements in genetics, and for leading the public project to sequence the Drosophila melanogaster genome. Related to his genomics work, Rubin's lab is notable for development of genetic and genomics tools and studies of signal transduction and gene regulation. Rubin also serves as a vice president of the Howard Hughes Medical Institute and executive director of the Janelia Research Campus.

Transposons are semi-parasitic DNA sequences which can replicate and spread through the host's genome. They can be harnessed as a genetic tool for analysis of gene and protein function. The use of transposons is well-developed in Drosophila and in Thale cress and bacteria such as Escherichia coli.

The history of genetics can be represented on a timeline of events from the earliest work in the 1850s, to the DNA era starting in the 1940s, and the genomics era beginning in the 1970s.

Transposon silencing is a form of transcriptional gene silencing targeting transposons. Transcriptional gene silencing is a product of histone modifications that prevent the transcription of a particular area of DNA. Transcriptional silencing of transposons is crucial to the maintenance of a genome. The “jumping” of transposons generates genomic instability and can cause extremely deleterious mutations. Transposable element insertions have been linked to many diseases including hemophilia, severe combined immunodeficiency, and predisposition to cancer. The silencing of transposons is therefore extremely critical in the germline in order to stop transposon mutations from developing and being passed on to the next generation. Additionally, these epigenetic defenses against transposons can be heritable. Studies in Drosophila, Arabidopsis thaliana, and mice all indicate that small interfering RNAs are responsible for transposon silencing. In animals, these siRNAS and piRNAs are most active in the gonads.

DNA transposons are DNA sequences, sometimes referred to "jumping genes", that can move and integrate to different locations within the genome. They are class II transposable elements (TEs) that move through a DNA intermediate, as opposed to class I TEs, retrotransposons, that move through an RNA intermediate. DNA transposons can move in the DNA of an organism via a single-or double-stranded DNA intermediate. DNA transposons have been found in both prokaryotic and eukaryotic organisms. They can make up a significant portion of an organism's genome, particularly in eukaryotes. In prokaryotes, TE's can facilitate the horizontal transfer of antibiotic resistance or other genes associated with virulence. After replicating and propagating in a host, all transposon copies become inactivated and are lost unless the transposon passes to a genome by starting a new life cycle with horizontal transfer. It is important to note that DNA transposons do not randomly insert themselves into the genome, but rather show preference for specific sites.

Tc1/mariner is a class and superfamily of interspersed repeats DNA transposons. The elements of this class are found in all animals, including humans. They can also be found in protists and bacteria.

hAT transposons are a superfamily of DNA transposons, or Class II transposable elements, that are common in the genomes of plants, animals, and fungi.

<i>Drosophila neotestacea</i> Species of fly

Drosophila neotestacea is a member of the testacea species group of Drosophila. Testacea species are specialist fruit flies that breed on the fruiting bodies of mushrooms. These flies will choose to breed on psychoactive mushrooms such as the Fly Agaric Amanita muscaria. Drosophila neotestacea can be found in temperate regions of North America, ranging from the north eastern United States to western Canada.

References

  1. 1 2 Orr-Weaver, T. (2003). "The 2003 George W. Beadle Medal; Gerald M. Rubin and Allan C. Spradling". Genetics. 164 (4): 1248–1249. doi:10.1093/genetics/164.4.1248. PMC   1462668 . PMID   15106662.
  2. 1 2 3 4 "Howard Hughes Medical Institute Investigators: Allan C. Spradling, Ph.D." Retrieved 2009-10-25.
  3. Spradling, A.; Rubin, G. (1982). "Transposition of cloned P elements into Drosophila germ line chromosomes". Science. 218 (4570): 341–347. Bibcode:1982Sci...218..341S. doi:10.1126/science.6289435. PMID   6289435.
  4. 1 2 Jedicke, Peter (2001). Extreme science: transplanting your head and other feats of the future. New York: St. Martin's Griffin. ISBN   978-0-312-26819-0.
  5. Rubin, G.; Spradling, A. (1982). "Genetic transformation of Drosophila with transposable element vectors". Science. 218 (4570): 348–353. Bibcode:1982Sci...218..348R. doi:10.1126/science.6289436. PMID   6289436.
  6. Spradling, A.; Drummond-Barbosa, D.; Kai, T. (2001). "Stem cells find their niche". Nature. 414 (6859): 98–104. Bibcode:2001Natur.414...98S. doi:10.1038/35102160. PMID   11689954. S2CID   2904709.
  7. Spradling, A.; Stern, D.; Beaton, A.; Rhem, E.; Laverty, T.; Mozden, N.; Misra, S.; Rubin, G. (1999). "The Berkeley Drosophila Genome Project gene disruption project: Single P-element insertions mutating 25% of vital Drosophila genes". Genetics. 153 (1): 135–177. doi:10.1093/genetics/153.1.135. PMC   1460730 . PMID   10471706.
  8. "APS Member History". search.amphilsoc.org. Retrieved 2021-02-18.
  9. Wiley Prize in Biomedical Sciences 2024