GEPHE SUMMARY Print
Gephebase Gene
Entry Status
Published
GepheID
GP00001883
Main curator
Courtier
PHENOTYPIC CHANGE
Trait Category
Trait State in Taxon A
Amaranthus palmeri - sensitive
Trait State in Taxon B
Amaranthus palmeri - resistant
Ancestral State
Taxon A
Taxonomic Status
Taxon A
Common Name
-
Synonyms
Amaranthus palmeri S.Watson
Rank
species
Lineage
Show more ... reptophyta; Streptophytina; Embryophyta; Tracheophyta; Euphyllophyta; Spermatophyta; Magnoliopsida; Mesangiospermae; eudicotyledons; Gunneridae; Pentapetalae; Caryophyllales; Amaranthaceae; Amaranthus
NCBI Taxonomy ID
is Taxon A an Infraspecies?
No
Taxon B
Common Name
-
Synonyms
Amaranthus palmeri S.Watson
Rank
species
Lineage
Show more ... reptophyta; Streptophytina; Embryophyta; Tracheophyta; Euphyllophyta; Spermatophyta; Magnoliopsida; Mesangiospermae; eudicotyledons; Gunneridae; Pentapetalae; Caryophyllales; Amaranthaceae; Amaranthus
NCBI Taxonomy ID
is Taxon B an Infraspecies?
No
GENOTYPIC CHANGE
UniProtKB
Arabidopsis thaliana
GenebankID or UniProtKB
Presumptive Null
No
Molecular Type
Aberration Type
Insertion Size
10-100 kb
Molecular Details of the Mutation
Genomes of resistant plants contain from 5-fold to more than 160-fold more copies of the EPSPS gene than did genomes of susceptible plants - the duplicated section of DNA including the 10 kb EPSPS gene is at least 30 kb long
Experimental Evidence
Authors
Gaines TA; Zhang W; Wang D; Bukun B; Chisholm ST; Shaner DL; Nissen SJ; Patzoldt WL; et al. ... show more
Abstract
The herbicide glyphosate became widely used in the United States and other parts of the world after the commercialization of glyphosate-resistant crops. These crops have constitutive overexpression of a glyphosate-insensitive form of the herbicide target site gene, 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). Increased use of glyphosate over multiple years imposes selective genetic pressure on weed populations. We investigated recently discovered glyphosate-resistant Amaranthus palmeri populations from Georgia, in comparison with normally sensitive populations. EPSPS enzyme activity from resistant and susceptible plants was equally inhibited by glyphosate, which led us to use quantitative PCR to measure relative copy numbers of the EPSPS gene. Genomes of resistant plants contained from 5-fold to more than 160-fold more copies of the EPSPS gene than did genomes of susceptible plants. Quantitative RT-PCR on cDNA revealed that EPSPS expression was positively correlated with genomic EPSPS relative copy number. Immunoblot analyses showed that increased EPSPS protein level also correlated with EPSPS genomic copy number. EPSPS gene amplification was heritable, correlated with resistance in pseudo-F(2) populations, and is proposed to be the molecular basis of glyphosate resistance. FISH revealed that EPSPS genes were present on every chromosome and, therefore, gene amplification was likely not caused by unequal chromosome crossing over. This occurrence of gene amplification as an herbicide resistance mechanism in a naturally occurring weed population is particularly significant because it could threaten the sustainable use of glyphosate-resistant crop technology.
Additional References
RELATED GEPHE
Related Genes
No matches found.
Related Haplotypes
No matches found.
COMMENTS
The EPSPS gene is present on all chromosomes
YOUR FEEDBACK is welcome!