James Birchler | |
---|---|
Born | |
Citizenship | United States |
Education | Eastern Illinois University, Indiana University Bloomington [1] |
Known for | Gene dosage, Minichromosomes |
Scientific career | |
Fields | Genetics, Plant Biology, Cytology |
Institutions | Harvard University, University of Missouri |
Thesis | "Biochemical studies on aneuploids of Zea mays L." (1977) |
Doctoral advisor | Drew Schwartz |
Website | ipg |
James A. Birchler is an American biologist who is currently Curators' Professor at University of Missouri where he studies gene dosage, polyploidy, and cytogenetics in both maize and drosophila. In 2002 he was named a fellow of the American Association for the Advancement of Science. [2] and in 2011 he was elected to the National Academy of Sciences. [3] [1] In 2017 he was named the SEC Professor of the Year. [4]
Birchler was born on a farm near Red Bud, Illinois. He attended Eastern Illinois University where he initially majored in education and was mentored by ethnobotanist Charles Arzeni. After completing his degree at EIU in 1972, ultimately majoring in biology with a minor in zoology, he moved to Indiana University Bloomington where he studied maize dosage effects using B chromosomes with Drew Schwartz, graduating in 1977. [5] Between 1978 and 1985 he worked as a postdoc studying gene dosage mechanisms in fruit flies, first at Oak Ridge National Laboratory with Ed Grell, and then at the University of California, Berkeley with Kenneth Paigen. In 1985 he was hired as an assistant professor at Harvard University, and in 1991 he moved to the University of Missouri. [1]
Birchler is known for his contributions to the study of gene dosage, dosage compensation, and gene balance using both maize (Zea mays) and fruit flies (Drosophila melanogaster) as model organisms. [3] He is also known for his lab's contributions to maize karyotyping by "chromosome painting" or fluorescence in situ hybridization. Birchler and his lab have also leveraged this tool and maize B-A chromosomal translocations to study the function and inactivation of centromeres. Birchler's lab also developed the first engineered minichromosomes in plants, by using telomere repeat sequences to truncate B chromosomes in maize. [6] James A. Birchler also developed Fast-Flowering Mini-Maize [7] as a small, rapid-cycling model for maize.
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.
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.
Hermann Joseph Muller was an American geneticist who was awarded the 1946 Nobel Prize in Physiology or Medicine, "for the discovery that mutations can be induced by X-rays". Muller warned of long-term dangers of radioactive fallout from nuclear war and nuclear testing, which resulted in greater public scrutiny of these practices.
Cytogenetics is essentially a branch of genetics, but is also a part of cell biology/cytology, that is concerned with how the chromosomes relate to cell behaviour, particularly to their behaviour during mitosis and meiosis. Techniques used include karyotyping, analysis of G-banded chromosomes, other cytogenetic banding techniques, as well as molecular cytogenetics such as fluorescence in situ hybridization (FISH) and comparative genomic hybridization (CGH).
George Wells Beadle was an American geneticist. In 1958 he shared one-half of the Nobel Prize in Physiology or Medicine with Edward Tatum for their discovery of the role of genes in regulating biochemical events within cells. He also served as the 7th President of the University of Chicago.
Seymour Benzer was an American physicist, molecular biologist and behavioral geneticist. His career began during the molecular biology revolution of the 1950s, and he eventually rose to prominence in the fields of molecular and behavioral genetics. He led a productive genetics research lab both at Purdue University and as the James G. Boswell Professor of Neuroscience, emeritus, at the California Institute of Technology.
Dosage compensation is the process by which organisms equalize the expression of genes between members of different biological sexes. Across species, different sexes are often characterized by different types and numbers of sex chromosomes. In order to neutralize the large difference in gene dosage produced by differing numbers of sex chromosomes among the sexes, various evolutionary branches have acquired various methods to equalize gene expression among the sexes. Because sex chromosomes contain different numbers of genes, different species of organisms have developed different mechanisms to cope with this inequality. Replicating the actual gene is impossible; thus organisms instead equalize the expression from each gene. For example, in humans, female (XX) cells randomly silence the transcription of one X chromosome, and transcribe all information from the other, expressed X chromosome. Thus, human females have the same number of expressed X-linked genes per cell as do human males (XY), both sexes having essentially one X chromosome per cell, from which to transcribe and express genes.
Marcus Morton Rhoades was an American cytogeneticist.
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.
A minichromosome is a small chromatin-like structure resembling a chromosome and consisting of centromeres, telomeres and replication origins but little additional genetic material. They replicate autonomously in the cell during cellular division. Minichromosomes may be created by natural processes as chromosomal aberrations or by genetic engineering.
X hyperactivation refers to the process in Drosophila by which genes on the X chromosome in male flies become twice as active as genes on the X chromosome in female flies.
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 served as a vice president of the Howard Hughes Medical Institute (2003–2020) and founding executive director of its Janelia Research Campus.
Barbara J. Meyer is a biologist and genetist, noted for her pioneering research on lambda phage, a virus that infects bacteria; discovery of the master control gene involved in sex determination; and studies of gene regulation, particularly dosage compensation. Meyer's work has revealed mechanisms of sex determination and dosage compensation—that balance X-chromosome gene expression between the sexes in Caenorhabditis elegans that continue to serve as the foundation of diverse areas of study on chromosome structure and function today.
Joachim Wilhelm "Jo" Messing was a German-American biologist who was a professor of molecular biology and the fourth director of the Waksman Institute of Microbiology at Rutgers University.
Norbert Perrimon is a French geneticist and developmental biologist. He is the James Stillman Professor of Developmental Biology in the Department of Genetics at Harvard Medical School, an Investigator at the Howard Hughes Medical Institute, and an Associate of the Broad Institute. He is known for developing a number of techniques for used in genetic research with Drosophila melanogaster, as well as specific substantive contributions to signal transduction, developmental biology and physiology.
Chao-ting Wu is an American molecular biologist. After training at Harvard Medical School in genetics with William Gelbart, at Stanford Medical School with David Hogness, and in a fellowship at Massachusetts General Hospital in molecular biology, Wu began her independent academic career as an assistant professor in Anatomy and Cellular Biology and then Genetics at Harvard Medical School in 1993. After a period as Professor of Pediatrics in the Division of Molecular Medicine at the Boston Children's Hospital, she returned to the Department of Genetics at Harvard Medical School as a full professor in 2007.
The McClintock Prize for Plant Genetics and Genome Studies is a prize awarded in genetics and genomics. The Prize is awarded by the Maize Genetics Executive Committee, and is presented to the Prize winner each spring at the Annual Maize Genetics Conference.
Subhash Chandra Lakhotia is an Indian cytogeneticist, academic, Distinguished Professor of Zoology, and the Science & Engineering Research Board (SERB) Distinguished Fellow at the Banaras Hindu University. He is known for his pioneering research on Drosophila with regard to its chromosome organization and replication. A Raja Ramanna fellow of the Department of Science and Technology and the Department of Atomic Energy, he is an elected fellow of all three major Indian science academies: Indian National Science Academy, Indian Academy of Sciences and National Academy of Sciences, India. He is a Senior Fellow of the Cell Stress Society International (USA). The Council of Scientific and Industrial Research, the apex agency of the Government of India for scientific research, awarded him the Shanti Swarup Bhatnagar Prize for Science and Technology, one of the highest Indian science awards, in 1989, for his contributions to biological sciences.
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.
Thomas Charles Kaufman is an American geneticist. He is known for his work on the zeste-white region of the Drosophila X chromosome. He is currently a Distinguished Professor of biology at Indiana University, where he conducts his current research on Homeotic Genes in evolution and development.