Genetics, Vol. 154, 437-446, January 2000, Copyright © 2000

Maize Reveal Multiple Mechanisms for Suppression

Lisa Girarda and Michael Freelinga
a Department of Plant and Microbial Biology, University of California, Berkeley, California 94720

Corresponding author: Michael Freeling, University of California, Berkeley, Department of Plant and Microbial Biology, 111 Koshland Hall, Berkeley, CA 94720., freeling{at}nature.berkeley.edu (E-mail)

Communicating editor: J. A. BIRCHLER

Insertions of Mutator transposons into maize genes can generate suppressible alleles. Mu suppression is when, in the absence of Mu activity, the phenotype of a mutant allele reverts to that of its progenitor. Here we present the characterization of five dominant Mu-suppressible alleles of the knox (knotted1-like homeobox) genes liguleless3 and rough sheath1, which exhibit neomorphic phenotypes in the leaves. RNA blot analysis suggests that Mu suppression affects only the neomorphic aspect of the allele, not the wild-type aspect. Additionally, Mu suppression appears to be exerting its effects at the level of transcription or transcript accumulation. We show that truncated transcripts are produced by three alleles, implying a mechanism for Mu suppression of 5' untranslated region insertion alleles distinct from that which has been described previously. Additionally, it is found that Mu suppression can be caused by at least three different types of Mutator elements. Evidence presented here suggests that whether an allele is suppressible or not may depend upon the site of insertion. We cite previous work on the knox gene kn1, and discuss our results in the context of interactions between Mu-encoded products and the inherently negative regulation of neomorphic liguleless3 and rough sheath1 transcription.





This article has been cited by other articles:


Home page
GeneticsHome page
M. L. Robbins, R. S. Sekhon, R. Meeley, and S. Chopra
A Mutator Transposon Insertion Is Associated With Ectopic Expression of a Tandemly Repeated Multicopy Myb Gene pericarp color1 of Maize
Genetics, April 1, 2008; 178(4): 1859 - 1874.
[Abstract] [Full Text] [PDF]


Home page
Proc. Natl. Acad. Sci. USAHome page
B. P. May, H. Liu, E. Vollbrecht, L. Senior, P. D. Rabinowicz, D. Roh, X. Pan, L. Stein, M. Freeling, D. Alexander, et al.
Maize-targeted mutagenesis: A knockout resource for maize
PNAS, September 30, 2003; 100(20): 11541 - 11546.
[Abstract] [Full Text] [PDF]


Home page
Proc. Natl. Acad. Sci. USAHome page
B. Shen, C. Li, Z. Min, R. B. Meeley, M. C. Tarczynski, and O.-A. Olsen
sal1 determines the number of aleurone cell layers in maize endosperm and encodes a class E vacuolar sorting protein
PNAS, May 27, 2003; 100(11): 6552 - 6557.
[Abstract] [Full Text] [PDF]


Home page
GeneticsHome page
X. Cui, A.-P. Hsia, F. Liu, D. A. Ashlock, R. P. Wise, and P. S. Schnable
Alternative Transcription Initiation Sites and Polyadenylation Sites Are Recruited During Mu Suppression at the rf2a Locus of Maize
Genetics, February 1, 2003; 163(2): 685 - 698.
[Abstract] [Full Text] [PDF]