The FIE3 (ftz instability element 3′) element is an RNA element found in the

3′ UTR In molecular genetics, the three prime untranslated region (3′-UTR) is the section of messenger RNA (mRNA) that immediately follows the translation termination codon. The 3′-UTR often contains regulatory regions that post-transcriptionally ...

of the fushi tarazu

mRNA In molecular biology, messenger ribonucleic acid (mRNA) is a single-stranded molecule of RNA that corresponds to the genetic sequence of a gene, and is read by a ribosome in the process of Protein biosynthesis, synthesizing a protein. mRNA is ...

. The fushi tarazu gene is essential for the establishment of the

Drosophila ''Drosophila'' () is a genus of flies, belonging to the family Drosophilidae, whose members are often called "small fruit flies" or (less frequently) pomace flies, vinegar flies, or wine flies, a reference to the characteristic of many species ...

embryonic body plan. When first expressed in early

embryogenesis An embryo is an initial stage of development of a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sperm ...

, fushi tarazu mRNA is uniformly distributed over most of the

embryo An embryo is an initial stage of development of a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male spe ...

. Subsequently, fushi tarazu mRNA expression rapidly evolves into a pattern of seven stripes that encircle the embryo. The instability of fushi tarazu mRNA may contribute to the localization of this pattern of

expression Expression may refer to: Linguistics * Expression (linguistics), a word, phrase, or sentence * Fixed expression, a form of words with a specific meaning * Idiom, a type of fixed expression * Metaphorical expression, a particular word, phrase, o ...

, but this is unlikely to be a dominant effect since the 744 base-pair ftz zebra stripe element can drive the ectopic expression of a reporter construct (with mRNA structure entirely unrelated to the ftz transcript) in a qualitatively highly similar pattern. Experiments provide evidence for at least two destabilizing elements in the fushi tarazu mRNA, one located within the

5′ Directionality, in molecular biology and biochemistry, is the end-to-end chemical orientation of a single strand of nucleic acid. In a single strand of DNA or RNA, the chemical convention of naming carbon atoms in the nucleotide pentose-sugar-ri ...

one-third of the mRNA and the other near the

3′ end Directionality, in molecular biology and biochemistry, is the end-to-end chemical orientation of a single strand of nucleic acid. In a single strand of DNA or RNA, the chemical convention of naming carbon atoms in the nucleotide pentose-sugar-ri ...

(termed FIE3 for ftz instability element 3′). The FIE3 lies within a 201-

nucleotide Nucleotides are organic molecules consisting of a nucleoside and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecules wi ...

sequence just upstream of the

polyadenylation Polyadenylation is the addition of a poly(A) tail to an RNA transcript, typically a messenger RNA (mRNA). The poly(A) tail consists of multiple adenosine monophosphates; in other words, it is a stretch of RNA that has only adenine bases. In euk ...

signal and can act autonomously to destabilize a heterologous mRNA. Further

deletion Deletion or delete may refer to: Computing * File deletion, a way of removing a file from a computer's file system * Code cleanup, a way of removing unnecessary variables, data structures, cookies, and temporary files in a programming language * ...

constructs identified an essential 68-nucleotide element within the FIE3. Although this element is predicted to contain a secondary structure, it also contains a GU rich sequence (UGUUUUGUUU) that is similar to GU rich instability elements subsequently identified in other systems.

References

External links

* RNA {{molecular-cell-biology-stub