Extrachromosomal DNA and cell differentiation in cultured pea roots (Pisum sativum)

Conference · Wed Jan 01 00:00:00 EST 1986

OSTI ID:5451504

Van't Hof, J

Histological, cytological and molecular analyses of DNA replication and differentiation and meristematic precursors of vascular parenchyma in cultured pea roots show that the initial steps in the transition from a dividing to a differentiated cell involve retardation of DNA replication in late S phase and production of extrachromosomal molecules by excision from late replicating chromosomal DNA. Portions of the extrachromosomal DNA are displaced by a strand displacement mechanism thereby producing free single-stranded molecules. That extrachromosomal molecules have rDNA reflects the fact that in pea roots replication of the ribosomal genes is maximal during late S phase (unpublished results). It is likely, therefore, that the excised late replicating DNA contains some rDNA sequences. 30 refs., 3 figs.

• Research Organization: Brookhaven National Lab., Upton, NY (USA). Biology Dept.
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 5451504
• Report Number(s): BNL-38406; CONF-8608101-1; ON: DE86014764
• Resource Relation: Conference: 6. international congress on plant tissue and cell culture: extrachromosomal DNA and cell differentiation in cultured pea roots (Pisum Sativum), St. Paul, MN, USA, 3 Aug 1986; Other Information: Portions of this document are illegible in microfiche products
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
CELL DIFFERENTIATION
BIOCHEMISTRY
AUTORADIOGRAPHY
PISUM
ROOTS
THYMIDINE
TRITIUM COMPOUNDS
AZINES
BACTERIA
CHEMISTRY
HETEROCYCLIC COMPOUNDS
LABELLED COMPOUNDS
LEGUMINOSAE
MICROORGANISMS
NUCLEOSIDES
NUCLEOTIDES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PLANTS
PYRIMIDINES
RHIZOBIUM
RIBOSIDES
550201* - Biochemistry- Tracer Techniques
550801 - Morphology- Tracer Techniques