Award#0421671 - Functional Genomics of Maize Centromeres

ABSTRACT

Centromeres are large chromosome domains that organize and regulate chromosome

movement. They contain thousands of simple repeated sequences and hundreds of

RNA-based transposable elements, all of which are difficult to sequence and manipulate in the

laboratory. Despite these challenges, mammalian centromeric DNA has been exploited to create

'artificial chromosomes' that can carry long segments of engineered DNA. Artificial chromosomes

could also have widespread applications in agriculture. For instance, entire biochemical

pathways or multiple disease resistances could be introduced simultaneously. The experiments

carried out under this award will fill major gaps in our understanding of plant centromeres and build

the foundation for creating artificial chromosomes in maize and rice. The resulting

information will be distributed through online resources and published articles that are readily available

in the public domain.

To expand training opportunities in plant genetics, two new programs will be initiated.

One will combine existing on-campus minority involvement programs and establish a

plant biology genomics focus at the University of Georgia. Hands-on training in plant

cytogenetics will also be offered through an Annual Cytogenetics Training Workshop (ACTW) at the

University of Wisconsin. The ACTW will provide training in fluorescent in situ

hybridization,immunolocalization, chromatin immunoprecipitation, and other advanced techniques

necessary for chromosome-based research.

Lamb J.C., Kato A., Birchler J.A.. "Sequences associated with A chromosome centromeres are present throughout the maize B chromosome.," Chromosoma, v.113, 2004, p. 337.

Lamb, J.C,. Meyer, J.M., Corcoran, B., Kato A., Han, F., and Birchler, J.A.. "Distinct chromosomal distributions of highly repetitive sequences in maize," Chromosome Research, v.15, 2007, p. 337.

Lamb, J.C., Han, F., Yu W., and Birchler, J.A.. "Plant chromosomes from end to end: telomeres, heterochromatin and centromeres," Current Opin. Plant Biol., v.103, 2007, p. 116.

Lamb, J.C., Kato, A., and Birchler, J.A.. "Centromere associated sequences are present throughout the maize B chromosome," Chromosoma, v.113, 2005, p. 337.

Lamb, J.C., Meyer, J.M., and Birchler, J.A.. "A hemicentric inversion in the maize line knobless Tama flint created two sites of centromeric elements and moved the kinetochore-forming region," Chromosoma, v.116, 2007, p. 237.

Lamb, JC; Yu, WC; Han, FP; Birchler, JA. "Plant chromosomes from end to end: telomeres, heterochromatin and centromeres," CURRENT OPINION IN PLANT BIOLOGY, v.10, 2007, p. 116-122.

Luce, A., Sharma, A., Mollere, O.S.B., Wolfgruber, T.K., Nagaki, K., Jiang, J., Presting, G.G., Dawe, R.K.. "Precise centromere mapping using a combination of repeat Junction markers and ChIP-PCR.," Genetics, v.174, 2006, p. 1057.

Phan B.H., Jin, W., Topp, C.N., Zhong, C.X., Jiang, J., Dawe R.K., and Parrott, W.A.. "Insertion of >100 kb centromeric repeat arrays into the rice genome by biolistic DNA transfer.," Transgenic Research, v.Nov., 2006, p. 000.

Phelps-Durr, T. and James A. Birchler, J.A.. "An asymptotic determination of minimum centromere size for the maize B chromosome.," Cytogenet. Genome Res., v.106, 2004, p. 309.

Sharma, A; Presting, GG. "Centromeric retrotransposon lineages predate the maize/rice divergence and differ in abundance and activity," MOLECULAR GENETICS AND GENOMICS, v.279, 2008, p. 133-147.

Topp, C.N., and Dawe, R.K.. "Reinterpreting pericentromeric heterochromatin.," Curr. Opin. Plant Biol., v.9, 2006, p. 647.

Topp, C.N., Zhong C.X., and Dawe, R.K.. "Centromere-encoded RNAs are integral components of the maize kinetochore.," Proc. Natl. Acad. Sci., v.101, 2004, p. 15986.

Yu, W., Han, F., Kato, A. and Birchler, J.A.. "Characterization of a maize isochromosome 8S.S.," Genome, v.49, 2006, p. 700.

Yu, WC; Han, FP; Gao, Z; Vega, JM; Birchler, JA. "Construction and behavior of engineered minichromosomes in maize," PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, v.104, 2007, p. 8924-8929.

Zhang, W.L., Lee, H.-R., Koo, D.-H., and Jiang, J.. "Epigenetic modification of centromeric chromatin: Hypomethylation of DNA sequences in the CENH3-associated chromatin in Arabidopsis thaliana and maize," Plant Cell, v.20, 2008, p. 25.

Zhang, X., Li, X., Marshall, J.B., Zhong, C.X., and Dawe, R.K.. "Phosphoserines on maize CENTROMERIC HISTONE H3 and histone H3 define the centromere and pericentromere during chromosome segregation.," Plant Cell 17, v.17, 2005, p. 572.