Genetic Functions Required For Gene Silencing In Maize
- Technology Benefits
- Genetic stocks that prevent the establishment or maintenance of transgene silencing are useful for engineering and breeding of new corn linesprevention of undesirable gene silencing in plants and in tissue culture
- Technology Application
- alleviation of undesirable transgene silencing in breeding and genetic engineering of corn
- Detailed Technology Description
- None
- Supplementary Information
- Patent Number: US7264970B2
Application Number: US2001972805A
Inventor: Chandler, Vicki L. | Hollick, Jay B. | Dorweiler, Jane E. | Lisch, Damon | Kubo, Ken | Carey, Charles
Priority Date: 5 Oct 2000
Priority Number: US7264970B2
Application Date: 5 Oct 2001
Publication Date: 4 Sep 2007
IPC Current: C12N001582 | A01H000100 | A01H000500 | A01H000510 | C12N000514
US Class: 435468 | 435412 | 435419 | 4354301 | 800266 | 800275 | 800298 | 8003201
Assignee Applicant: The Regents of the University of California | University of Oregon,Eugene | University of Arizona,Tucson
Title: Genetic functions required for gene silencing in maize
Usefulness: Genetic functions required for gene silencing in maize
Summary: The mutant plants with reduced gene silencing activity are useful in producing transgenic plants and seeds where the transgene remains active in subsequent generations (claimed).
Novelty: Mutant corn plants, useful in the generation of transgene active transgenic plants, comprise mutations that reduce the establishment or maintenance of paramutation
- Industry
- Biomedical
- Sub Category
- DNA/Gene Engineering
- Application No.
- 7264970
- Others
-
Tech ID/UC Case
16955/2000-081-0
Related Cases
2000-081-0
- *Abstract
-
Hollick, Jay B.; Chandler, Vicki L.
Genetic factors required to maintain repression of a paramutagenic maize pl1 allele.
Genetics. January, 2001. 157(1):369-378.
Abstract:
A genetic screen identified two novel gene functions required to maintain mitotically and meiotically heritable gene silencing associated with paramutation of the maize purple plant 1 (pl1) locus. Paramutation at pl1 leads to heritable alterations of pl1 gene regulation; the Pl-Rhoades (Pl-Rh) allele, which typically confers strong pigmentation to juvenile and adult plant structures, changes to a lower expression state termed Pl'-mahogany (Pl'). Paramutation spontaneously occurs at low frequencies in Pl-Rh homozygotes but always occurs when Pl-Rh is heterozygous with Pl'. We identified four mutations that caused increased Pl' pigment levels. Allelism tests revealed that three mutations identified two new maize loci, required to maintain repression 1 (rmr1) and rmr2 and that the other mutation represents a new allele of the previously described mediator of paramutation 1 (mop1) locus. RNA levels from Pl' are elevated in rmr mutants and genetic tests demonstrate that Pl' can heritably change back to Pl-Rh in rmr mutant individuals at variable frequencies. Pigment levels controlled by two pl1 alleles that do not participate in paramutation are unaffected rmr mutants. These results suggest that RMR functions are intimately involved in maintaining the repressed expression state of paramutant Pl' alleles. Despite strong effects on Pl' repression, rmr mutant plants have no gross developmental abnormalities even after several generations of inbreeding, implying that RMR1 and RMR2 functions are not generally required for developmental homeostasis.
also see:
Dorweiler, Jane E.; Carey, Charles C.; Kubo, Kenneth M.; Hollick, Jay B.;
Kermicle, Jerry L.; Chandler, Vicki L.
mediator of paramutation1 is required for establishment and maintenance of paramutation at multiple maize loci.
Plant Cell. November, 2000. 12(11):2101-2118.
Abstract:
Paramutation is the directed, heritable alteration of the expression of one allele when heterozygous with another allele. Here, the isolation and characterization of a mutation affecting paramutation, mediator of paramutation1-1 (mop1-1), are described. Experiments demonstrate that the wild-type gene Mop1 is required for establishment and maintenance of the paramutant state. The mop1-1 mutation affects paramutation at the multiple loci tested but has no effect on alleles that do not participate in paramutation. The mutation does not alter the amounts of actin and ubiquitin transcripts, which suggests that the mop1 gene does not encode a global repressor. Maize plants homozygous for mop1-1 can have pleiotropic developmental defects, suggesting that mop1-1 may affect more genes than just the known paramutant ones. The mop1-1 mutation does not alter the extent of DNA methylation in rDNA and centromeric repeats. The observation that mop1 affects paramutation at multiple loci, despite major differences between these loci in their gene structure, correlations with DNA methylation, and stability of the paramutant state, suggests that a common mechanism underlies paramutation. A protein-based epigenetic model for paramutation is discussed.
- *IP Issue Date
- Sep 4, 2007
- *Principal Investigator
-
Name: CHARLES CAREY
Department:
Name: VICKI CHANDLER
Department:
Name: JANE DORWEILER
Department:
Name: Jay Hollick
Department:
Name: KENNETH KUBO
Department:
Name: Damon Lisch
Department:
- Country/Region
- USA
