The flg-Rhizobiales RNA motif is an RNA

RNA

Ribonucleic acid , or RNA, is one of the three major macromolecules that are essential for all known forms of life....

 structure that is conserved in certain bacteria

Bacteria

Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...

. All known flg-Rhizobiales RNAs are located in the presumptive 5' untranslated regions of operon

Operon

In genetics, an operon is a functioning unit of genomic DNA containing a cluster of genes under the control of a single regulatory signal or promoter. The genes are transcribed together into an mRNA strand and either translated together in the cytoplasm, or undergo trans-splicing to create...

s that contain gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

s whose functions relate to the creation of flagellar basal bodies. The flg-Rhizobiales RNAs are restricted to the Rhizobiales

Rhizobiales

Rhizobiales is an order of alpha proteobacteria. They are gram-negative.The rhizobia, which fix nitrogen and are symbiotic with plant roots, appear in several different families here. The Bradyrhizobiaceae, Hyphomicrobiaceae, Phyllobacteriaceae, and Rhizobiaceae are the four families that contain...

, an order

Order (biology)

In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...

 of alphaproteobacteria

Alphaproteobacteria

Alphaproteobacteria is a class of Proteobacteria. Like all Proteobacteria, they are Gram-negative.-Characteristics:The Alphaproteobacteria comprise most phototrophic genera, but also several genera metabolising C1-compounds , symbionts of plants and animals, and a group of pathogens, the...

, although only some Rhizobiales bacterial are predicted to use flg-Rhizobiales RNAs. The exact function of these RNAs is unknown, although it is hypothesized that they have a cis-regulatory

Cis-regulatory element

A cis-regulatory element or cis-element is a region of DNA or RNA that regulates the expression of genes located on that same molecule of DNA . This term is constructed from the Latin word cis, which means "on the same side as". These cis-regulatory elements are often binding sites for one or...

function in controlling expression of the downstream operons.