A maize root tip system to study DNA replication programmes in somatic and endocycling nuclei during plant development.
The progress of nuclear DNA replication is complex in both time and space, and may reflect several levels of chromatin structure and 3-dimensional organization within the nucleus. To understand the relationship between DNA replication and developmental programmes, it is important to examine replication and nuclear substructure in different developmental contexts including natural cell-cycle progressions in situ. Plant meristems offer an ideal opportunity to analyse such processes in the context of normal growth of an organism. Our current understanding of large-scale chromosomal DNA replication has been limited by the lack of appropriate tools to visualize DNA replication with high resolution at defined points within S phase. In this perspective, we discuss a promising new system that can be used to visualize DNA replication in isolated maize (Zea mays L.) root tip nuclei after in planta pulse labelling with the thymidine analogue, 5-ethynyl-2'-deoxyuridine (EdU). Mixed populations of EdU-labelled nuclei are then separated by flow cytometry into sequential stages of S phase and examined directly using 3-dimensional deconvolution microscopy to characterize spatial patterns of plant DNA replication. Combining spatiotemporal analyses with studies of replication and epigenetic inheritance at the molecular level enables an integrated experimental approach to problems of mitotic inheritance and cellular differentiation.
Department of Biological Science, Florida State University, Tallahassee, FL 32306-4295, USA.
Hank W
HW
Bass
Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695, USA.
Emily E
EE
Wear
Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695, USA.
Tae-Jin
TJ
Lee
Department of Biological Science, Florida State University, Tallahassee, FL 32306-4295, USA.
Gregg G
GG
Hoffman
Department of Biological Science, Florida State University, Tallahassee, FL 32306-4295, USA.
Hardeep K
HK
Gumber
Department of Horticultural Science, North Carolina State University, Raleigh, NC 27695, USA.
George C
GC
Allen
Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695, USA.
William F
WF
Thompson
Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC 27695, USA linda_hanley-bowdoin@ncsu.edu.
Linda
L
Hanley-Bowdoin
D001483:Base Sequence; D002467:Cell Nucleus / Q000235:genetics; D004261:DNA Replication; D018744:DNA, Plant / Q000096:biosynthesis*; D017404:In Situ Hybridization, Fluorescence; D015345:Oligonucleotide Probes; D018517:Plant Roots / Q000254:growth & development*; D003313:Zea mays / Q000235:genetics / Q000254:growth & development*
D018744:DNA, Plant; D015345:Oligonucleotide Probes
DNA replication; EdU; S phase.; endocycle; flow cytometry; high-resolution microscopy; maize; mitotic cell cycle; root development