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Plant Genetic Engineer



"Plant genetic engineer" is a popular term that describes scientists working in any of several fields who manipulate DNA or organelles such as chloroplasts and mitochondria in plant cells. The specific titles of such a scientist can include plant physiologist, plant pathologist, weed scientist, cell biologist, botanist, molecular biologist, plant geneticist, and biochemist. The typical career path is to earn a doctorate in any of these fields, and then to go to work in industry, for the government, or in academia.



Jobs that involve genetic manipulation of plants are also available at the technician level. This requires a bachelor's or master's degree in any of the fields listed above. As of 2001, the median salary for an academic life scientist is $42,000, and for a scientist in industry, $70,000. Technician salaries begin at about $25,000. Government salaries are similar to academic compensation.

Scientists work with plant genes in basic research as well as in developing new crops. In basic research, a plant may serve as a model system, enabling researchers to study a fundamental structure or function at the cellular or molecular level. The mustard plant Arabidopsis thaliana is the most popular plant model system. Most work on this plant is not to alter or develop a product from it, but to study its basic biology and then extrapolate what is learned to other plant species. Similarly, Zea mays (corn) was used extensively in the mid-twentieth century to reveal how chromosomes interact as a cell divides. Today, entire genomes of plants and other types of organisms are being sequenced, which is enabling researchers to work with several genes at a time. The genomes of Arabidopsis and several major crop plants are being sequenced.

Some plant scientists manipulate genes to create new variants. Adding a gene from another species forms a transgenic organism. For example, "bt corn" plants harbor a gene from a bacterium that enables plant cells to produce a toxin that kills certain insect larvae that feed on the leaves. "Golden rice" produces beta carotene, a precursor to vitamin A, which is not naturally abundant in the grain portion of this plant. The ability to manufacture beta carotene comes from three genes, taken from daffodils and a bacterium, that specify enzymes that interact in a biochemical pathway, along with genetic instructions to express the genes in the grain, so that it can serve as a vitamin-enriched food.

A plant genetic engineer must be familiar with the characteristics that distinguish plants from other types of organisms. Unlike animal cells, plant cells have tough cell walls, which must be penetrated to reach the DNA. Also, some genetic material resides in the organelles called plastids, the largest of which is the chloroplast. The engineer must also be able to regenerate an altered plant cell into a plant, test that plant in a greenhouse, and, finally, see how well it flourishes in a field environment. For example, tomato plants can be given a gene from A. thaliana that enables them to grow in very salty water. Developers of such a crop must analyze how the plant that can now grow in brackish or salty water will affect other types of plants that normally grow in that environment. Thus, in addition to understanding genetics, molecular biology, and biochemistry, a plant genetic engineer working on an agricultural variant must also have expertise in plant development and The tissue removed from this sunflower plant will be used in genetic research at the Sungene Technologies Laboratory in Palo Alto, California. ecology.

Ricki Lewis

Bibliography

Palevitz, Barry A. "Corn Goes Pop, Then Kaboom." Scientist 16 (2002): 18-19.

Stone, Richard. "Biologist Gets Under the Skin of Plants—and Peers." Science 296 (2002): 1597-1599.

Additional topics

Medicine EncyclopediaGenetics in Medicine - Part 3