NOVELTY - Gene expression cassette, is new, which enhances content of biofuel synthesis precursors in plant biomass and comprises: (a) at least one transcription regulating nucleotide sequence; and (b) at least one gene comprising a gene encoding sucrose isomerase, the sequence as given in the specification, a gene encoding amylase and/or a gene which suppresses starch synthesis.    USE - The gene expression cassette is useful for producing renewable fuel including biodiesel oil and/or ethanol (claimed).    DETAILED DESCRIPTION - Gene expression cassette, is new, which enhances content of biofuel synthesis precursors in plant biomass, as compared to unmodified plants and comprises: (a) at least one transcription regulating nucleotide sequence, where the transcription regulating nucleotide sequence is (i) a constitutive promoter, (ii) an inducible promoter, (iii) a tissue-specific promoter, (iv) a developmentally regulated promoter and/or (v) a nucleotide sequence which is the complement or reverse complement of any of the nucleotide sequences under (i) to (iv), and functionally linked to it; and (b) at least one gene comprising (ia) a gene encoding sucrose isomerase, (iia) the sequence as given in the specification, (iiia) a gene encoding amylase and/or (iva) a gene which suppresses starch synthesis. INDEPENDENT CLAIMS are included for:    (1) a vector comprising the expression cassette;    (2) a genetically modified plant with enhanced content of biofuel precursors in plant biomass, as compared to unmodified plants and the genetically modified plant comprises the gene expression cassette;    (3) a feedstock for production of ethanol and/or biodiesel fuels comprising the genetically modified plant;    (4) a transgenic plant product, comprising propagation material, cells, organs, parts, cell cultures, seeds of transgenic progeny of the genetically modified plant;    (5) a genetically modified plant having an increased amount of sugar or biofuel as compared to a non-genetically modified plant, where the genetically modified comprises the gene expression cassette;    (6) a process of engineering high-biofuel plant biomass using genetically modified plants with elevated content of biofuel synthesis precursors, compared to unmodified plants, as a host plant for metabolic engineering of lipids, comprising (a1) introducing into the plant the gene expression cassette and (b1) selecting transgenic plants with elevated content of oil biofuel precursors;    (7) a process of producing a genetically modified plant with enhanced sugar content as compared to a corresponding control plant, comprising the step of (a1) as above per se and (b2) selecting transgenic plants with enhanced sugar content;    (8) a method of producing biodiesel or bioethanol, comprising the process, and the method further comprises the step of converting the biomass of the genetically modified plant to produce biodiesel or bioethanol; and    (9) a process of producing biodiesel and bioethanol comprising providing genetically modified plant biomass comprising the gene expression cassette and converting the plant biomass to biodiesel and bioethanol.