Carolyn Napoli

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Carolyn Napoli
Known forco-discovery of the mechanism of co-suppression
Scientific career
Fields Plant biology
Institutions University of Arizona

Carolyn Napoli is a plant biologist who co-discovered the mechanism of co-suppression, [1] gene silencing which, like transposon silencing, was first discovered in plants. The significance of the discovery of co-suppression was described by NOVA scienceNOW in 2005. [2]

Contents

Research and career

At the University of Florida, in the Soil Sciences Department laboratory of David H. Hubbell, Napoli demonstrated for the first time using electron microscopy, the development of infection by the soil bacterium, Rhizobium trifolii, in Trifolium (clover) root hairs. [3]

Napoli continued her Rhizobium research in the laboratory of Peter Albersheim [4] at the University of Colorado Boulder and later the lab of Larry Gold [5] in the Department of Molecular, Cellular and Developmental Biology. before leaving for the laboratory of Brian Staskawicz at University of California, Berkeley to work on plant avirulence genes. [6]

Transitioning from academia to industry, Napoli joined collaborator Richard A. Jorgensen at the Oakland-based agricultural biotechnology company Advanced Genetic Sciences, Inc. (AGS) which was acquired later by DNA Plant Technology Corporation. At AGS, Napoli and Jorgensen sought to increase flower pigmentation by overexpressing the gene encoding the Chalcone Synthase (CHS) by using a vector for high-level translation designed by their AGS colleague Jonathan Jones. The antisense CHS construct they deployed in Petunia plants created novel flower color distribution. One of these patterns, dubbed "Cossack Dancer," [7] was featured in The Plant Cell 30-year retrospective, "Refections on Plant Cell Classics,". [8] [9] These observations documented by Napoli and Jorgensen are examples of "co-suppression," [1] – a post transcriptional gene silencing mechanism predating the discovery of RNA interference (RNAi).

From DNAP, Napoli accepted a faculty position in the Department of Environmental Horticulture at the University of California, Davis (UCD) where she deployed a strategy of ethyl methanesulfonate (EMS) to produce mutations in both Petunia and Arabidopsis seeds. By screening over 1,200 mutants she identified a bushy phenotype that she termed "decreased apical dominance" or "dad" mutants and subsequently published her analysis of the reversal of this phenomenon by grafting in the journal Plant Physiology. [10] In collaboration with Loverine Taylor, Napoli identified a phenotype that was used as a selectable marker for plant breeding research. [11]

Following UCD, Napoli joined the Department of Plant Sciences at the University of Arizona (UA) where she focused on designing and distributing resources to the Arabidopsis and maize research communities under the auspices of an National Science Foundation Plant Genome Research Program [12] grant led by Jorgensen and Vicki Chandler. At UA, Napoli launched the NSF-funded ChromDB (Chromatin Database), [13] a platform for displaying chromatin-associated proteins, including RNAi-associated proteins, for a range of organisms.

Awards and honors

In 2023 Napoli was recognized as a Pioneer Member of the American Society of Plant Biologists. [14] [15]

References

  1. 1 2 Napoli, C.; Lemieux, C.; Jorgensen, R. (April 1, 1990). "Introduction of a Chimeric Chalcone Synthase Gene into Petunia Results in Reversible Co-Suppression of Homologous Genes in trans". The Plant Cell. 2 (4): 279–289. doi:10.1105/tpc.2.4.279. ISSN   1040-4651. PMC   159885 . PMID   12354959.
  2. "RNAi: A wayward petunia leads to the discovery of modest little molecules with enormous medical promise". NOVA scienceNOW . PBS. July 26, 2005. Retrieved November 12, 2024.
  3. Napoli, C A; Hubbell, D H (1975). "Ultrastructure of Rhizobium-induced infection threads in clover root hairs". Applied Microbiology. 30 (6): 1003–1009. doi:10.1128/am.30.6.1003-1009.1975. ISSN   0003-6919. PMC   376582 . PMID   1211931.
  4. Carlson, Russell W.; Sanders, Richard E.; Napoli, Carolyn; Albersheim, Peter (1978). "Host-Symbiont Interactions: III. Purification and Partial Characterization of Rhizobium Lipopolysaccharides". Plant Physiology. 62 (6): 912–917. doi:10.1104/pp.62.6.912. ISSN   0032-0889. JSTOR   4265561. PMC   1092253 . PMID   16660637.
  5. Napoli, Carolyn; Gold, Larry; Singer, Britta Swebilius (July 5, 1981). "Translational reinitiation in the rIIB cistron of bacteriophage T4" . Journal of Molecular Biology. 149 (3): 433–449. doi:10.1016/0022-2836(81)90480-0. PMID   7310886.
  6. Napoli, C; Staskawicz, B (February 1, 1987). "Molecular characterization and nucleic acid sequence of an avirulence gene from race 6 of Pseudomonas syringae pv. glycinea". Journal of Bacteriology. 169 (2): 572–578. doi:10.1128/jb.169.2.572-578.1987. ISSN   0021-9193. PMC   211816 . PMID   3027035.
  7. Scheid, Ortrun Mittelsten (June 12, 2019). "Illuminating (White and) Purple Patches". The Plant Cell. 31 (6): 1208–1209. Bibcode:2019PlanC..31.1208S. doi:10.1105/tpc.19.00308. ISSN   1040-4651. PMC   6588294 . PMID   31036597.
  8. "Reflections on Plant Cell Classics". May 15, 2019.
  9. Scheid, Ortrun Mittelsten (June 2019). "Illuminating (White and) Purple Patches". The Plant Cell. 31 (6): 1208–1209. Bibcode:2019PlanC..31.1208S. doi:10.1105/tpc.19.00308. ISSN   1040-4651. PMC   6588294 . PMID   31036597.
  10. Napoli, Carolyn (1996). "Highly Branched Phenotype of the Petunia dadl-7 Mutant 1s Reversed by Grafting". academic.oup.com. Retrieved May 18, 2024.
  11. Napoli, Carolyn A.; Fahy, Deirdre; Wang, Huai-Yu; Taylor, Loverine P. (June 1, 1999). "white anther : A Petunia Mutant That Abolishes Pollen Flavonol Accumulation, Induces Male Sterility, and Is Complemented by a Chalcone Synthase Transgene1". Plant Physiology. 120 (2): 615–622. doi:10.1104/pp.120.2.615. ISSN   1532-2548. PMC   59301 . PMID   10364414.
  12. "Plant Genome Research Program (PGRP) | NSF - National Science Foundation". February 16, 2024.
  13. Gendler, Karla; Paulsen, Tara; Napoli, Carolyn (January 1, 2008). "ChromDB: The Chromatin Database". Nucleic Acids Research. 36 (suppl_1): D298 –D302. doi:10.1093/nar/gkm768. ISSN   0305-1048. PMC   2238968 . PMID   17942414.
  14. "Pioneer Carolyn Napoli". American Society of Plant Biologists. Retrieved November 13, 2024.
  15. "Carolyn Napoli Testimonials". American Society of Plant Biologists. Retrieved November 13, 2024.