Methods controlling gene expression

摘要

The present invention is in the field of genetics, especially plant genetics, and provides agents capable of controlling gene expression. The present invention specifically provides sequences of naturally occurring, tissue-specifically expressed microRNAs. The invention further provides for transgenic expression constructs comprising sequences encoding said microRNAs. By incorporation of the microRNA encoding sequence the expression from said expression construct is specifically silenced in the tissue where the naturally occurring microRNA is naturally expressed. Thereby the expression profile resulting from the promoter is modulated and leakiness is reduced. The invention further provides for a method for modulating transgenic expression by incorporating sequences encoding said microRNAs into transgenic expression constructs. The compositions and methods of the invention can be used to enhance performance of agricultural relevant crops and for therapy, prophylaxis, research and diagnostics in diseases and disorders, which afflict mammalian species.

主权项

1. A method for suppressing or lowering expression of a chimeric nucleotide sequence in a plant, comprising the steps of:
a) providing an expression construct comprising a promoter sequence functional in a monocotyledonous plant and functionally linked thereto a chimeric nucleotide sequence to be expressed, wherein said chimeric nucleotide sequence comprises:
i) at least one sequence comprising an open reading frame encoding a protein that is capable of conferring an agronomically valuable trait in a plant, andii) at least one sequence substantially complementary to a microRNA sequence naturally occurring in said plant,wherein the at least one sequence of i) and the at least one sequence of ii) are heterologous to each other, b) introducing said expression construct into a plant, and c) expressing said chimeric nucleotide sequence in said plant, wherein the plant is a monocotyledonous crop plant, wherein the expression of said chimeric nucleotide sequence is suppressed or lowered in tissues where said naturally occurring microRNA is expressed, and wherein said chimeric nucleotide sequence expression is not suppressed or lowered in tissues where said naturally occurring microRNA is not expressed.