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Title: Extrachromosomal DNA of pea (Pisum sativum) root-tip cells replicates by strand displacement

Abstract

In cultured pea roots there is extrachromosomal DNA associated with cells that differentiate from the G/sub 2/ phase of the cell cycle that is absent from those that differentiate from the G/sub 1/ phase. The authors examined this extrachromosomal DNA by electron microscopy and found that it consisted of three types: (i) double-stranded linear molecules with single-stranded branches (74%), (ii) double-stranded molecules without branches (26%), and (iii) free single-stranded molecules. The double-stranded molecules with or without branches were similar in length, having a modal length of 10-15 ..mu..m. The free single-stranded molecules were shorter and had a mean length of 3.8 ..mu..m. The length of the branches attached to the duplex molecules was only slightly less than that of the free form. The duplex molecules with branches were interpreted as configurations reflecting an ongoing strand-displacement process that results in free single-stranded molecules. Finally, measurements on duplex molecules with multiple branches suggested that the extrachromosomal DNA may exist in the form of tandemly repeated sequences. 8 references, 8 figures.

Authors:
;
Publication Date:
Research Org.:
Brookhaven National Lab. (BNL), Upton, NY (United States)
OSTI Identifier:
6389970
Resource Type:
Journal Article
Journal Name:
Proc. Natl. Acad. Sci. U.S.A.; (United States)
Additional Journal Information:
Journal Volume: 80
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; DNA; MOLECULAR STRUCTURE; CELL DIFFERENTIATION; ELECTRON MICROSCOPY; EXPERIMENTAL DATA; MOLECULAR BIOLOGY; MOLECULES; PISUM; PLANT CELLS; ROOTS; BACTERIA; DATA; INFORMATION; LEGUMINOSAE; MICROORGANISMS; MICROSCOPY; NUCLEIC ACIDS; NUMERICAL DATA; ORGANIC COMPOUNDS; PLANTS; RHIZOBIUM; 550300* - Cytology

Citation Formats

Krimer, D B, and Van't Hof, J. Extrachromosomal DNA of pea (Pisum sativum) root-tip cells replicates by strand displacement. United States: N. p., 1983. Web. doi:10.1073/pnas.80.7.1933.
Krimer, D B, & Van't Hof, J. Extrachromosomal DNA of pea (Pisum sativum) root-tip cells replicates by strand displacement. United States. https://doi.org/10.1073/pnas.80.7.1933
Krimer, D B, and Van't Hof, J. 1983. "Extrachromosomal DNA of pea (Pisum sativum) root-tip cells replicates by strand displacement". United States. https://doi.org/10.1073/pnas.80.7.1933.
@article{osti_6389970,
title = {Extrachromosomal DNA of pea (Pisum sativum) root-tip cells replicates by strand displacement},
author = {Krimer, D B and Van't Hof, J},
abstractNote = {In cultured pea roots there is extrachromosomal DNA associated with cells that differentiate from the G/sub 2/ phase of the cell cycle that is absent from those that differentiate from the G/sub 1/ phase. The authors examined this extrachromosomal DNA by electron microscopy and found that it consisted of three types: (i) double-stranded linear molecules with single-stranded branches (74%), (ii) double-stranded molecules without branches (26%), and (iii) free single-stranded molecules. The double-stranded molecules with or without branches were similar in length, having a modal length of 10-15 ..mu..m. The free single-stranded molecules were shorter and had a mean length of 3.8 ..mu..m. The length of the branches attached to the duplex molecules was only slightly less than that of the free form. The duplex molecules with branches were interpreted as configurations reflecting an ongoing strand-displacement process that results in free single-stranded molecules. Finally, measurements on duplex molecules with multiple branches suggested that the extrachromosomal DNA may exist in the form of tandemly repeated sequences. 8 references, 8 figures.},
doi = {10.1073/pnas.80.7.1933},
url = {https://www.osti.gov/biblio/6389970}, journal = {Proc. Natl. Acad. Sci. U.S.A.; (United States)},
number = ,
volume = 80,
place = {United States},
year = {Fri Apr 01 00:00:00 EST 1983},
month = {Fri Apr 01 00:00:00 EST 1983}
}