Previous Article | Next Article ![]()
Applied and Environmental Microbiology, March 1999, p. 1268-1279, Vol. 65, No. 3
Institute of Molecular BioSciences,
Received 17 July 1998/Accepted 6 October 1998
Epichloë endophytes are a group of filamentous fungi that
include both sexual (Epichloë) and asexual
(Neotyphodium) species. As a group they are genetically
diverse and form both antagonistic and mutualistic associations with
temperate grasses. We report here on the development of a
microsatellite-based PCR system for fingerprinting this group of fungi
with template isolated from either culture or infected plant material.
M13mp19 partial genomic libraries were constructed for
size-fractionated genomic DNA from two endophyte strains. These
libraries were screened with a mixture of DIG-labeled dinucleotide and
trinucleotide repeat probes. Positive clones were sequenced, and nine
unique microsatellite loci were identified. An additional
microsatellite was serendipitously identified in the 3' untranscribed
region of the 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase
gene from N. lolii Lp19. Primers were designed for each
locus and a panel of endophytes, from different taxonomic groupings,
was screened to determine the degree of polymorphism. On the basis of
these results a multiplex assay was developed for strain identification
with fluorescently labeled primers for five of these loci. Using this
system the size of the products amplified can be precisely determined
by automated analysis, and an allele profile for each strain can be
readily generated. The assay was shown to resolve endophyte groupings
to the level of known isozyme phenotype groupings. In a blind test the
assay was used successfully to identify a set of endophytes in planta.
A reference database of allele sizes has been established for the panel
of endophytes examined, and this will be expanded as new strains are analyzed.
0099-2240/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.
Identification of Epichloë Endophytes In
Planta by a Microsatellite-Based PCR Fingerprinting Assay with
Automated Analysis
*
Corresponding author. Mailing address: Institute of
Molecular BioSciences, Massey University, Private Bag 11222, Palmerston North, New Zealand. Phone: 64-6-350-4033. Fax: 64-6-350-5688. E-mail: d.b.scott{at}massey.ac.nz.
Applied and Environmental Microbiology, March 1999, p. 1268-1279, Vol. 65, No. 3
0099-2240/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»