# US 10,246,719 B2 · Modulating laccase enzyme to regulate cell wall biosynthesis and recalcitrance in plants > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,246,719 B2 - Document ID: US10246719B2 - Status: Granted - Kind: B2 - Application number: 15/647,819 - Filed: 2017-07-12 - Published: 2018-01-18 - Granted: 2019-04-02 - Earliest claimed: 2016-07-13 - Assignees: UT-Battelle, LLC - Applicants: UT-Battelle, LLC - Inventors: Jin-Gui Chen; Lee E. Gunter; Sara S. Jawdy; Xiaohan Yang; Gerald A. Tuskan; Anthony Christian Bryan - Web page: https://patentgrep.com/patent/US10246719B2 ## CPC - C12N 15/8255: {involving lignin biosynthesis} - C07K 14/415: from plants - C12N 5/04: Plant cells or tissues {(culture media C12N5/0025)} - C12N 9/0061: {Laccase (1.10.3.2)} - C12N 15/52: Genes encoding for enzymes or proenzymes - C12N 15/8213: {Targeted insertion of genes into the plant genome by homologous recombination} - C12N 15/8218: {Antisense, co-suppression, viral induced gene silencing [VIGS], post-transcriptional induced gene silencing [PTGS]} - C12Q 1/68: involving nucleic acids - C12Q 1/6895: for plants, fungi or algae - C12Q 2600/13: Plant traits - C12N: MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA (microbiological testing media C12Q1/00) - C07K: PEPTIDES (peptides in foodstuffs A23; obtaining protein compositions for foodstuffs, working-up proteins for foodstuffs A23J; preparations for medicinal purposes A61K; peptides containing beta-lactam rings C07D; cyclic dipeptides not having in their molecule any other peptide link than those which form their ring, e.g. piperazine-2,5-diones, C07D; ergot alkaloids of the cyclic peptide type C07D519/02; macromolecular compounds having statistically distributed amino acid units in their molecules, i.e. when the preparation does not provide for a specific; but for a random sequence of the amino acid units, homopolyamides and block copolyamides derived from amino acids C08G69/00; macromolecular products derived from proteins C08H1/00; preparation of glue or gelatine C09H; single cell proteins, enzymes C12N; genetic engineering processes for obtaining peptides C12N15/00; compositions for measuring or testing processes involving enzymes C12Q; investigation or analysis of biological material G01N33/00) - C12Q: MEASURING OR TESTING PROCESSES INVOLVING ENZYMES, NUCLEIC ACIDS OR MICROORGANISMS (immunoassay G01N33/53); COMPOSITIONS OR TEST PAPERS THEREFOR; PROCESSES OF PREPARING SUCH COMPOSITIONS; CONDITION-RESPONSIVE CONTROL IN MICROBIOLOGICAL OR ENZYMOLOGICAL PROCESSES ## Abstract This disclosure provides genetically modified plants having desirable levels of sugar release and syringyl/guaiacyl (S/G) ratio; methods of genetically modifying plants to modulate sugar release and S/G ratio; and uses of such plants. The inventors have determined that genetic modification of a laccase gene (LAC2) from Populus, encoded by locus Potri.008G064000 resulted in transgenic Populus trees with changes in syringyl/guaiacyl ratios as well as altered sugar release phenotypes. Plants with altered sugar release, and S/G ratio, based on modulation of the expression or activity of the LAC2 gene, have divergent uses including pulp and paper production, and biofuel and bioproducts production. ## Claims ### Claim 1 A genetically modified plant characterized by a reduced expression of the LAC2 gene as compared to a control plant, wherein the genetic modification is specifically targeted at the LAC2 gene or the LAC2 mRNA to reduce the LAC2 gene expression. ### Claim 2 (depends on 1) The genetically modified plant of claim 1, wherein said genetically modified plant belongs to a genus selected from the group consisting of Populus, Manihot, Gossypium, Eucalyptus, Medicago, Arabidopsis, Solanum, Oryza and Zea. ### Claim 3 (depends on 2) The genetically modified plant of claim 2, wherein the plant is selected from the group consisting of Populus balsamifera, Populus deltoides, Populus trichocarpa, Populus tremuloides, Populus tremula, Populus alba and Populus maximowiczii. ### Claim 4 (depends on 1) The genetically modified plant of claim 1, wherein the reduced expression of the LAC2 gene is achieved by a method selected from the group consisting of introducing a nucleic acid inhibitor, the CRISPR/Cas system, the Cre/Lox system, the TALEN system, and homologous recombination. ### Claim 5 (depends on 4) The genetically modified plant of claim 4, wherein said nucleic acid inhibitor is selected from the group consisting of an antisense RNA, a small interfering RNA, an RNAi microRNA, an artificial microRNA, and a ribozyme. ### Claim 6 (depends on 1) A method for biofuel production, comprising using the plant of claim 1 in a biofuel fermentation process. ### Claim 7 An expression vector, comprising a nucleotide sequence that is transcribed into a nucleic acid inhibitor of expression of the LAC2 gene, operably linked to a regulatory region that is functional in a plant, wherein the nucleic acid is selected from the group consisting of an antisense RNA, a small interfering RNA, an RNAi microRNA, an artificial microRNA, and a ribozyme. ### Claim 8 (depends on 7) The expression vector of claim 7, wherein the regulatory region comprises an inducible promoter or a tissue-specific promoter. ### Claim 9 (depends on 8) The expression vector of claim 8 wherein the tissue-specific promoter is a xylem-specific promoter. ### Claim 10 (depends on 7) A method for increasing glucose and/or xylose release in a plant or plant cell, comprising introducing the expression vector of claim 7 in said plant or plant cell, and expressing the nucleic acid in plant or plant cell. ### Claim 11 (depends on 7) A plant or plant cell comprising the expression vector of claim 7.