Transposable Elements:
A Homage to Barbara McClintock and Hopi Zea mays
Intertwining her roles as citizen scientist, artist, and papermaker, Megan Singleton presents us with a new body of work investigating the connections between an innovative pioneering woman in corn science, Barbara McClintock, and the brilliant beauty of Hopi Zea mays (maize). In 2023, the Missouri Botanical Garden Horticulture team at the William T. Kemper Center for Home Gardening graciously grew a large plot of Hopi Turquoise and Hopi Purple maize for Singleton to use as material for her exhibition. Seeing
the cobs’ striking color pallets of indigo, purple, mauve, and blue that contrasted against the warm soft cream-colored husks inspired the artist’s desire to showcase the exquisiteness of heirloom genetic diversity in corn plants. In the search for the genetic sequence of these varieties, Singleton was introduced to the groundbreaking work of Nobel Prize winner, Barbara McClintock (1902-1992), an expert in maize cytogenetics who researched the behavior of maize kernel color and produced the first genetic map of
maize. McClintock then discovered transposition within the kernels’ genes, and used this to demonstrate genes are responsible for turning physical traits on or o , such as the variety of coloration patterns on corn cobs. Later, this revelation changed the manner in which scientists think about genetic patterns of inheritance. The genetic sequences of the Bz1 gene and C-gene were important and relevant to Barbara McClintock’s work, as well as to the purple colors in the Hopi lines. Corn expert and scientist Katie Murphy explains, “The Bz1 gene encodes a protein that actually makes pigment colors, and its presence or absence determines whether there is none, brown, or purple pigment. The C-gene encodes a 'transcription factor.’ I think of this as an on/o switch for other genes. When the C-gene is present and active, it will ‘turn on’ the Bz1 gene, among others. For an analogy, if Bz1 is the lightbulb, C is the light switch complete with the dimming function.” The installation Anthocyanin uses cast paper cobs to depict the sequence of this C-gene. Other works in the exhibition include sculpture, and installations using handmade paper and pulp made from the macerated corn fibers grown at the Garden, as well as photography and castings created using cobs from the Hopi Turquoise and Hopi Purple plants.
* Documentary Photo Credit Virginia Harold
the cobs’ striking color pallets of indigo, purple, mauve, and blue that contrasted against the warm soft cream-colored husks inspired the artist’s desire to showcase the exquisiteness of heirloom genetic diversity in corn plants. In the search for the genetic sequence of these varieties, Singleton was introduced to the groundbreaking work of Nobel Prize winner, Barbara McClintock (1902-1992), an expert in maize cytogenetics who researched the behavior of maize kernel color and produced the first genetic map of
maize. McClintock then discovered transposition within the kernels’ genes, and used this to demonstrate genes are responsible for turning physical traits on or o , such as the variety of coloration patterns on corn cobs. Later, this revelation changed the manner in which scientists think about genetic patterns of inheritance. The genetic sequences of the Bz1 gene and C-gene were important and relevant to Barbara McClintock’s work, as well as to the purple colors in the Hopi lines. Corn expert and scientist Katie Murphy explains, “The Bz1 gene encodes a protein that actually makes pigment colors, and its presence or absence determines whether there is none, brown, or purple pigment. The C-gene encodes a 'transcription factor.’ I think of this as an on/o switch for other genes. When the C-gene is present and active, it will ‘turn on’ the Bz1 gene, among others. For an analogy, if Bz1 is the lightbulb, C is the light switch complete with the dimming function.” The installation Anthocyanin uses cast paper cobs to depict the sequence of this C-gene. Other works in the exhibition include sculpture, and installations using handmade paper and pulp made from the macerated corn fibers grown at the Garden, as well as photography and castings created using cobs from the Hopi Turquoise and Hopi Purple plants.
* Documentary Photo Credit Virginia Harold