The 1997 GSA Honors and Awards
Total Page:16
File Type:pdf, Size:1020Kb
Copyright © 1998 by the Genetics Society of America The 1997 GSA Honors and Awards The Genetics Society of America makes two awards annually to honor members who have made out- standing contributions to the science of genetics. The Thomas Hunt Morgan Medal recognizes a lifetime contribution to genetics. The Genetics Society of America Medal recognizes particularly outstanding contributions to genetics within the past fifteen years. We are pleased to announce the 1997 awards. The 1997 Thomas Hunt Morgan Medal Oliver Evans Nelson, Jr. Oliver Evans Nelson, Jr. in the lab. Photo by B. Wolfgang Hoffmann. LIVER EVANS NELSON, JR. exemplifies a “life- tion. Here he worked with D. F. Jones, a well-known O time contribution to genetics.” His published work corn breeder and geneticist. His early interest in genet- spans a 50-year period and includes seminal contribu- ics was further developed by training he received under tions in several different areas of investigation. Al- E. W. Sinnott. Oliver completed his doctoral research though focused on maize, the results of his research under D. F. Jones at Yale in 1947 and thereupon as- have had profound and broad impact on agronomic sumed a faculty position at Purdue University where he genetics, physiological genetics of plants, and eukary- remained until 1969. During these years, he initiated a otic gene structure and function. successful popcorn breeding program—some of the Oliver was born in Seattle in 1920. After receiving lines he developed are still in commercial use. his early education in the New Haven area, he was in- In the 1950’s Oliver realized that the expression of troduced to genetics before starting college during a the waxy gene in pollen grains afforded a unique op- summer working as an assistant in the Department of portunity to screen very large numbers of gametes for Genetics, Connecticut Agricultural Experiment Sta- rare recombinants. Utilizing this system, he carried out Genetics 148: 1–6 ( January, 1998) 2 Honors and Awards the first fine structure analysis of a gene in higher bronze gene. This represented the first successful appli- plants. This was one of the first and most detailed stud- cation of transposon tagging in plants and established ies of its kind in any eukaryote. One of the important the bronze locus, with its many interesting alleles, as a discoveries from this investigation was the demonstra- model system for investigation of gene regulation in tion that transposable elements mapped throughout plants and the effect of transposable elements at the the gene long before such ideas were part of the ac- molecular level. cepted wisdom. Oliver’s fine structure work on waxy was Oliver also continued to pursue a long-standing in- undoubtedly stimulated by the analysis of the rII locus be- terest in the biosynthesis of starch. His earlier discovery ing conducted by his Purdue colleague, Seymour Benzer. that the waxy locus encoded a starch-bound ADP-glu- In turn, on a trip through the cornfields with Seymour, cose glucosyl transferase was one of the first to relate a Oliver drew Seymour’s attention to a nongeotropic mu- phenotypically identified plant gene with the underly- tant cornstalk crawling along the ground. This experi- ing enzymatic defect. Although for many years the ence helped convince Seymour to choose Drosophila topic received little attention, the importance of starch when he decided to work on behavioral genetics. in cereals, roots, and tubers as a major food source for Another of Oliver’s seminal contributions during humans and domesticated animals as well its impor- the Purdue years was the discovery, with biochemist Ed- tance as an industrial commodity have contributed to win T. Mertz, of mutants with a high content of lysine renewed interest in starch synthesis and its modifica- and tryptophan, thereby greatly enhancing the food tion through genetics and biotechnology. Most of what value of corn. This was no accidental discovery but the is currently known about the biochemical lesions re- outcome of a deliberate search based on Oliver’s deep sponsible for quantitative or qualitative alterations in knowledge of the corn kernel and the properties of the starch biosynthesis is based on mutations first identi- available mutants. Feeding studies with rats were re- fied in maize. Oliver and his students have been major markable. Laboratory rats grown on opaque-2 grew contributors to these studies. After his retirement in more than three times faster than rats fed on ordinary 1991, work on the bronze gene and on starch biosynthe- corn. This pioneering achievement led to further work sis continued to occupy Oliver’s attention. in other plants, such as sorghum, and in making plant Oliver has received numerous prestigious awards and breeders aware of the fact that nutritional quality could honors for his achievements including election to the Na- be improved through selection. The agricultural im- tional Academy of Sciences in 1972. Among his most last- pact of this pioneering achievement continues to be ing contributions are the numerous students and post- felt today. doctoral associates that he trained. In 1990 his former Early on, Oliver recognized the importance of being students and colleagues dedicated a commemorative is- able to characterize the enzymatic defect in various sue of Maydica, the specialty journal of maize genetics, to maize mutants to address problems of basic genetic sig- Oliver upon the occasion of his seventieth birthday. Ol- nificance, particularly those concerned with gene struc- iver joins other luminaries, including R. A. Brink, Edward ture, function, and regulation. He worked toward this Coe, Marcus Rhoades, and Barbara McClintock (all of aim beginning with a sabbatical in 1954 at the Bio- whom were themselves recipients of the Thomas Hunt chemical Institute at the University of Stockholm. He Morgan Medal), in being honored with such a commem- continued this pursuit with another sabbatical leave in orative issue. The respect, admiration, and affection with 1961 at the California Institute of Technology. His sub- which Oliver is regarded by his students and associates is sequent biochemical studies on the biosynthesis of quite apparent in this commemorative issue. starch, lignin, protein, and anthocyanin in seeds were Oliver has never avoided taking on extra responsibil- one outcome of these sabbaticals. Another was his mar- ities. He served as Chair of the Laboratory of Genetics riage to Gerda in 1963 after making her acquaintance from 1986 to 1989 and for many years was the local or- first in Stockholm and then crossing paths with her ganizer of the annual maize genetics conference. In his again later in California. Perhaps unsurprisingly, Oliver free time, Oliver enjoyed life in the country and out- has not been permitted another sabbatical since. door activities. Over the years, he has been an avid In 1969, Oliver moved to the Laboratory of Genetics golfer, gardener, and companion to golden retrievers. at the University of Wisconsin, to fill the vacancy cre- As a scientist, Oliver’s enormous contributions to ag- ated upon the retirement of R. A. Brink. Fortunately, riculture and to basic genetics, his clarity of vision, and Brink’s retirement was an active one and the interac- his deep knowledge and insights have been an inspira- tions between Nelson and Brink provided a fertile and tion and an example for others to follow. As a person, stimulating environment for the training of new gener- in his modest demeanor and in his comportment al- ations of corn geneticists. Beginning in the late 1960s, ways as a gentleman, Oliver is also worthy of respect Oliver focused on developing a system in which the ef- and emulation. This year’s Thomas Hunt Morgan fect of transposable elements on the function of a gene Medal honors the remarkable achievements of a re- could be assayed at the protein level. In collaboration markable man. with Nina Fedoroff, Oliver’s laboratory cloned the Barry Ganetzky Honors and Awards 3 The 1997 Genetics Society of America Medal Christine Guthrie Christine Guthrie in 1991. Photo by Bill Santos. HRISTINE GUTHRIE’s outstanding contributions force. Although many questions about the relevance of C to the understanding of nuclear premessenger yeast snRNAs to events in mammalian cells remained, RNA splicing have been recognized with the awarding future events would reveal Christine’s pioneering work of the 1997 Genetics Society of America Medal. In the in this area to be foundational to the understanding of 20 years since the unanticipated presence of introns in both premessenger RNA splicing and eukaryotic preri- eukaryotic genes was revealed, no one else has applied bosomal RNA processing. “the awesome power of yeast genetics” more consis- In addition to leading the chase for cellular factors tently and successfully to the how and why of splicing. that might carry out splicing, Christine and her col- Confronted with the challenge to identify the ma- leagues created intron-containing reporter genes chinery and mechanisms of intron removal, and whose expression depended on splicing. The yeast ac- charged by the provocative hypothesis that small nu- tin intron served as a model, and tests of mutations in clear RNAs (snRNAs) might be involved in splicing, the conserved splice sites and branchpoint sequences Christine and her colleagues set out in the early ’80s within the intron revealed a complex set of molecular to discover whether yeast might have snRNAs. Using phenotypes: some mutations blocked splicing com- antibodies against the unusual vertebrate snRNA cap pletely, others allowed only the first steps of splicing, structure and a clever labeling strategy that got around still others shifted the splicing reactions to alternate the presence of contaminating degradation products, sites (Cellini et al. 1986; Parker and Guthrie 1985; Christine showed that yeast has a diverse family of Vijayraghavan et al.