Carolyn Napoli is a botanist 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]

Research and career

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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

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

References

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  1. ^ a b Napoli, C.; Lemieux, C.; Jorgensen, R. (1990-04-01). "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. PMID 16660637.
  5. ^ Napoli, Carolyn; Gold, Larry; Singer, Britta Swebilius (5 July 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 (1 February 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 (12 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.
  8. ^ "Reflections on Plant Cell Classics". 15 May 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 2024-05-18.
  11. ^ Napoli, Carolyn A.; Fahy, Deirdre; Wang, Huai-Yu; Taylor, Loverine P. (1999-06-01). "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". 16 February 2024.
  13. ^ Gendler, Karla; Paulsen, Tara; Napoli, Carolyn (2008-01-01). "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 2024-11-13.
  15. ^ "Carolyn Napoli Testimonials". American Society of Plant Biologists. Retrieved 2024-11-13.