plant animal and fungal mitochondria the bacterium mycoplasma capricolumn or the ciliate macronucleus may be used when the nucleic acid is expressed therein when the nucleic acid is prepared or altered synthetically advantage can be taken of known codon preferences of the intended host organism for example although nucleic acid sequences of the present invention may be expressed in both monocotyledonous and dicotyledonous plant species sequences can be modified to account for the specific codon preferences and gc content preferences of monocotyledons or dicotyledons as these preferences have been shown to differ murray et al 1989 nucl acids res 17 477 498 thus the maize preferred codon for a particular amino acid may be derived from known gene sequences from maize maize codon usage for 28 genes from maize plants is listed in table 4 of murray et al supra as used herein u201c full length sequence u201d in reference to a specified polynucleotide or its encoded protein means having the entire amino acid sequence of a native non synthetic endogenous biologically e g structurally or catalytically active form of the specified protein methods to determine whether a sequence is full length are well known in the art including such exemplary techniques as northern or western blots primer extension s1 protection and ribonuclease protection see e g plant molecular biology a laboratory manual clark ed springer verlag berlin 1997 comparison to known full length homologous orthologous and or paralogous sequences can also be used to identify full length sequences of the present invention additionally consensus sequences typically present at the 5 u2032 and 3 u2032 untranslated regions of mrna aid in the identification of a polynucleotide as full length for example the consensus sequence annnn aug g where the underlined codon represents the n terminal.