Neil Butt N.J.Butt at sussex.ac.uk
Mon Nov 14 06:57:58 EST 1994

Thanks to all who replied to my endoreduplication query. Here is a
summary of all the replies I received.


endoreduplication (or ploidy increases) in Arabidopsis leaves has been described
by Arumuganathan and Earle, Plant Molecular Reporter 9,208 (1991)
        We have described the in situ expression pattern of histone H2A which
matches S phase cells (Tanimoto et al, Plant Physiol. 103,1291 (1993); Koning et
al, Plant Cell 3, 657 (1991). By this approach, we observed endoreduplicating
cells in roots of pea and tomato. Most plants show extensive endoreduplication
in root cells. I have not directly tested genes which are not activated during
endoreduplication (I think you mean they are off), but there must be several,
such as agamous, leafy and others. However, with pea we used a control cDNA
whose expression is "constitutive" and is unaffected by S-phase cycling.
Luca Comai

Hi: I dont really know anything about this except that Arabidopsis 
has quite a few polyploid cells in leaves.  Gerd Jurgens also 
published a paper in cell recently showing that some trichomes have 
DNA amounts up to 8X - perhaps this is endoreduplication?

Dear Neil:

See:  Science 220:1049-1051 (1983) for tobacco
      Plant Physiology 96:985-989 (1991) for Arabidopsis

You might also be interested in Science 250:99-101 (1990).

Get back to me if you have any questions;  I'm off to Italy for the next
two weeks.

Best wishes

David Galbraith


        Did you see a paper in The Plant Journal (1994) vol 6(1): 55-66.
They discuss about endoreplication in Tobacco (Nicotiana plumbaginifolia).

S.P. Dinesh-Kumar (Dr. Baker lab)
Plant Gene Expression Center
Albany, CA 94710, USA


You may want to look at trichomes.  Trichomes in A. th undergo three rounds of 
endoreduplication prior to terminal differentiation.  Some of the trichome 
mutants block these events.  Try David Marks at the University of Minnesota-

Jeffrey Jeddeloh
Department of Biology (Box 1137)
Washington University
One Brookings Dr.
St Louis, MO 63117
(314) 935-7592
email: jeddeloh at biodec.wustl.edu

Three references on endopolyploidy in Arabidopsis are:

Galbraith et al. (1991) Plant Physiol. 96, 985-989.
Melaragno et al. (1993) Plant Cell 5, 1661-1668.
Hulskamp et al. (1994) Cell 76, 555-566.

Best wishes, Elliot Meyerowitz


About endoreduplication see:  Melaragno et al. (1993) Relationship
between endopolyploidy and cell size in epidermal tissue of 
Arabidopsis.  Plant Cell 5:1661-1668.

Would you let me know if this helped.  I have not before answered 
a request to the newsgroup.


Steve Gantt
Department of Plant Biology
University of Minnesota
Hi Neil,

There's a paper on systemic endopolyploidy in Arabidopsis in Plant
Physiology 96:985-989 (1991) which might be of interest.

Brian Keith

You should contact David Galbraith of the University of Arizona for
comments on this.  Bob Price

Dear Neil,  you might try getting in touch with David Galbraith at the 
Dept. of Plant Sciences in Tucson.  He published a paper on 
endoredupication in Arabidopsis (Plant Physiol. 96:985-989, 1991) and may 
have the information you require.

Yours sincerely,  Alan Slusarenko
Alan Slusarenko
Institute of Plant Biology
Zollikerstr. 107
Ch-8008 Zurich

Tel. **41 1 385 4250   FAX **41 1 385 4204
e-mail  slusi at botinst.unizh.ch

how you doing. re your question there was a paper by knapp and galbraith
in plant phys. about endoreduplication in arabidopsis cells a couple of years
ago, but it was mainly flow cytometer measurements of C levels in different
cell types.  that may be of some relevance although it didnt 
mention molecules much!

all the best
kevin Pyke

Dear Neil,

I remenber there was a paper in Plant physiol. in 1991 or 1992 (possilbly 
one of the authors was Galbraith or similar: work on Arabidopsis.

Hope thAt helps,
 Tony Schaeffner
Institut f. Biochemie, University of Munich, germany

Dear Neil,
There is a paper in Plant Cell Vol.5. 1661-1668 Nov. 1993 about
"Relationship between Endoploidy and Cell size in Epidermal Tissue of
Arabidopsis" and citations within this paper.
An other paper looking at the ploidy level of Trichomes of A. th. is
from M. Huelskamp, S. Misera and G. Juergens in Cell this Februrary
or March.
There is evidence that a protein kinase inhibitor K252a induces high
polyploidy (Nagl. W., 1993, Plant Cell Rep. 12, 170-174).
But you found probably this references already.
I am interested in the answers you get from other people too.
I was a postdoc in Phil Benfey's Lab in New York working on root
develompent and especially cell expansions.
Now during a new screen for root expansion mutants in A.th. I found
some with multi nuclei or giant nuclei as well. Now I start building
my own group in Vienna and would like to start characterizing this
mutant group.
I hope we could stay in contact and I would like more information
about your project and these preliminary results.
Best regards,
Marie-Theres Hauser

Dr. Marie-Theres Hauser
Center of applied Genetics
Universitaet fuer Bodenkultur
Gregor Mendel Str. 33
A-1180 Vienna
Tel.: +43-1-47654-2252 or 2258
FAX: +43-1-57654-2292
e-mail: hauser at mail.boku.ac.at

Neil-I believe Tom Rost (UC Davis) has published on endoreduplication in 
All the best,
Richard Cyr

Dear Dr.Butt:
Dr.Bill Park At Texas A&M Unviersity  Dept. of Biochem/Biophysics 
would be an excellent canidate. 

In article <395v79$or4 at mserv1.dl.ac.uk> you wrote:
: Dear netters

: I was wondering if anyone has investigated endoreduplication in
: Arabidopsis or tobacco. We have some data which may show this in tobacco
: roots if our interpretation of results is correct. In terms of the cell
: cycle the plant replicates its DNA without the cells dividing at
: mitosis. I was wondering if anyone has information on which genes are
: not activated at this stage, so we can use them as controls. The
: literature is very sparse on the molecular aspect of this process
: hence the request.

This occurs in pericycle cells of root, according to the literature.  Are
these the cells you are studying?  I am also interested in lateral root
formation in arab., and it has been suggested that the pericyle arrest
in G2 iallows fast lateral formation in response to stimuli.  I can come
up with references if this has anything to do with what you're doing


Dear Neil,

        I am currently investigating whether endoreduplication in the
cotyledons of Arabidopsis is effected by ultraviolet-B radiation in an effort
to explain the morphological changes which I have been reporting for
a number of years. So I am quite keen on this topic. I'll mention a couple of
books and papers which you may well be aware of, but just in case here they

Nagl, Walter (1978) Endopolyploidy and Polyteny in Differentiation and
Evolution. North-Holland Publishing, Amsterdam, 283 p.

Brodsky V. Ya. and I.V. Uryvaeva (1985) Genome Multiplication in Growth and
Development. Cambridge University Press, London, 305 p.

Galbraith DW, KR Harkins, S Knapp (1991) Systematic endopolyploidy in
Arabidopsis thaliana. Plant Physiol 96:985-989

Galbraith DW, KR Harkins, JM Maddox, NM Ayres, DP Sharm, E Firoozabady (1983)
Rapid flow cytometric analysis of the cell cycle in intact plants. Science 220:

De Rocher EJ,KR Harkins, DW Galbraith, HJ Bonhert (1990) Developmentally
regulated systematic endopolyploidy in succulents with small genomes. Science

Nagl W (1976) DNA endoreduplication and polyteny understood as evolutionary
strategies. Nature 261:614-615

I'd like to stay in touch, let me know how you're doing if you like.

Cheers for now!

Michael I Wilson
Department of Biology
University of Waterloo
Waterloo, Ontario
Canada N2L 3G1
Fax 1-519-746-0416
Phone 1-519-885-1211 ext 3827

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