Michael Levine (biologist)

Last updated
Michael S. Levine
Nationality American
Alma mater University of California, Berkeley (BA)
Yale University (PhD)
Known for Homeobox, eve stripe-2, ascidian developmental biology
Awards NAS Award in Molecular Biology (1996)
Scientific career
Fields Developmental biology
Institutions Princeton University
University of California, Berkeley
University of California, San Diego
Columbia University
Doctoral advisor Alan Garen
Doctoral students Albert Erives
Notes
Member of the National Academy of Sciences (1998)

Michael Levine is an American developmental and cell biologist at Princeton University, where he is the Director of the Lewis-Sigler Institute for Integrative Genomics and a Professor of Molecular Biology. [1] [2]

Contents

Levine previously held appointments at the University of California, Berkeley, the University of California, San Diego, and Columbia University. He is notable for co-discovering the Homeobox in 1983 and for discovering the organization of the regulatory regions of developmental genes. [3]

Biography

Levine was born in West Hollywood and raised in Los Angeles. [3] Levine studied biology as an undergraduate at UC Berkeley, studying biology with Allan Wilson [3] and graduating in 1976. [4] He went on to graduate studies at Yale, where he studied with Alan Garen and in 1981 received a Ph.D. in molecular biophysics and biochemistry. [4]

Levine joined the Princeton faculty in 2015, and had been a professor at UC Berkeley after leaving UCSD in 1996. [5]

Discoveries

Homeobox discovery

Levine was a post-doc with Walter Gehring in Switzerland from 1982 to 1983. [6] There, he co-discovered the homeobox with Ernst Hafen and fellow post-doc William McGinnis: [7]

After learning that Ultrabithorax, a gene that specifies the development of wings, showed a localized pattern of expression similar to that of Antennapedia, they decided to revisit the classic papers of Ed Lewis. In 1978, Lewis had proposed that all these homeotic genes (the ones that tell animals where to put a wing and where to put a leg and so on) arose from a common ancestral gene. So McGinnis carved up the Antennapedia gene and, using those pieces as probes, the trio identified eight genes, which turned out to be the eight homeotic genes in flies. "That pissed off a lot of people," says Levine. "The homeotic genes were the trophies of the Drosophila genome. And we got 'em all. I mean, we got 'em all!" Far from being humble, Levine says, "We were like, 'We kicked your ass pretty good, didn't we, baby!' Those were the days." [3]

Discovery of the eve stripe 2 enhancer

Levine briefly returned to UC Berkeley as a postdoctoral fellow [4] with Gerry Rubin. [8] He then joined the faculty of Columbia University, where he "led the discovery of the modular organization of the regulatory regions of developmental genes." [9] After isolating the even-skipped (eve) gene, Levine's team determined that each of the seven stripes was produced by separate enhancers. [3] With further study they discovered that both a set of activators and a set of repressors worked together to shape the expression of eve in the second stripe, and determined that the repressors shut down only their binding enhancers, leaving other enhancers free of repression. [3] Joseph Corbo said of the work,

"Before Levine's studies of even-skipped stripe 2, it wasn't clear how you generated spatially restricted patterns of gene expression from initially broad crude gradients of morphogens. I think that the even-skipped stripe 2 studies were the defining studies that showed how an organism can interpret those gradients and turn them into specific patterns of gene expression. To me that's Mike's crowning achievement." [3]

Discoveries in the ascidian Ciona

After earning tenure in only four years at Columbia, [3] Levine moved to UCSD in 1991, [4] where he added the sea squirt, Ciona intestinalis , to his repertoire. Although much of Levine's work, including his homeobox studies, has been done in Drosophila [6] Levine's team is also prominent in work with the sea squirt, Ciona intestinalis , an invertebrate that facilitates study of development. [3] For example, this work included insights into classical myodeterminants [10] [11] [12] and the composition of the notochord, the defining tissue of the chordate phylum. [13]

Awards

Professional relations

Levine cites as a significant influence his instructor Fred Wilt (taking his developmental biology class "was probably the single most galvanizing experience I had in terms of defining my future goals"), [8] and cites fellow scientists Eric Davidson, Peter Lawrence and Christiane Nusslein-Volhard as "mentors [and] friends ... over the years". [8]

On choosing to become a research biologist, he described some family pressure to become a doctor ("Coming from a modest background, particularly a Jewish family, the pressure to become a doctor was intense"), [3]

Fellow biologist Sean Carroll said of Levine, "Mike's work has done for animal development what the work on the lac operon and phage lambda did for understanding gene regulation in simpler organisms ... [Those] two big discoveries had a very large conceptual significance for developmental biology and by extension for evolutionary biology." [9]

Notable papers


Notes

  1. "Molecular Biology Faculty Michael Levine".
  2. "LSI History".
  3. 1 2 3 4 5 6 7 8 9 10 Hopkin, Karen (March 1, 2007). "Fire Fly". The Scientist. 21 (3): 58.
  4. 1 2 3 4 UCSD Press Release, April 30, 1996.
  5. 1 2 Wilbur Cross Medal 2009 Winners Bios, Yale University (last visited 2012 July 29) ("The Wilbur Lucius Cross Medal is an honor presented each year by the Graduate School Alumni Association to a small number of outstanding alumni. The medal recognizes distinguished achievements in scholarship, teaching, academic administration, and public service–all areas in which the legendary Dean Cross excelled.")
  6. 1 2 "What have you got in common with a fly?", Science Museum, South Kensington, UK (last visited July 29, 2012).
  7. McGinnis, W.; Levine, M. S.; Hafen, E.; Kuroiwa, A.; Gehring, W. J. (1984). "A conserved DNA sequence in homoeotic genes of the Drosophila Antennapedia and bithorax complexes". Nature. 308 (5958): 428–33. Bibcode:1984Natur.308..428M. doi:10.1038/308428a0. PMID   6323992. S2CID   4235713.
  8. 1 2 3 4 Mike Levine (Abstract), Current Biology , v.13, n.14, R545 (July 15, 2003).
  9. 1 2 Sean B. Carroll, quoted in Hopkin, Karen (March 1, 2007). "Fire Fly". The Scientist. 21 (3): 58.
  10. Erives, Albert; Levine, Michael (2001). "Ci-sna cis-Regulation of Ascidian Tail Muscle Genes". The Biology of Ascidians. pp. 193–201. doi:10.1007/978-4-431-66982-1_30. ISBN   978-4-431-66984-5.
  11. Erives, Albert; Levine, Michael (2000). "Characterization of a Maternal T-box Gene in Ciona intestinalis". Developmental Biology. 225 (1): 169–78. doi: 10.1006/dbio.2000.9815 . PMID   10964472.
  12. Erives, Albert; Corbo, Joseph C.; Levine, Michael (1998). "Lineage-Specific Regulation of the Ciona snail Gene in the Embryonic Mesoderm and Neuroectoderm". Developmental Biology. 194 (2): 213–25. doi: 10.1006/dbio.1997.8810 . PMID   9501022.
  13. Takahashi, H.; Hotta, K.; Erives, A.; Di Gregorio, A.; Zeller, R. W.; Levine, M.; Satoh, N. (1999). "Brachyury downstream notochord differentiation in the ascidian embryo". Genes & Development. 13 (12): 1519–23. doi:10.1101/gad.13.12.1519. PMC   316807 . PMID   10385620.
  14. "Michael Levine", Searle Scholars Program directory. (last visited July 29, 2012).
  15. "90 Scientists and Economists Win Sloan Research Awards", New York Times , March 10, 1985.
  16. "NAS Award in Molecular Biology" Archived 2012-07-22 at the Wayback Machine , National Academy of Sciences (Awarded for recent notable discovery in molecular biology by a young scientist age 45 or younger).
  17. "Michael S. Levine", National Academy of Sciences Member Directory (last visited 2012 July 29).
Seminars and Talks
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