The Spot 42 RNA is a non-coding RNA

Non-coding RNA

A non-coding RNA is a functional RNA molecule that is not translated into a protein. Less-frequently used synonyms are non-protein-coding RNA , non-messenger RNA and functional RNA . The term small RNA is often used for short bacterial ncRNAs...

 molecule

Molecule

A molecule is an electrically neutral group of at least two atoms held together by covalent chemical bonds. Molecules are distinguished from ions by their electrical charge...

 discovered over three decades ago. Escherichia coli

Escherichia coli

Escherichia coli is a Gram-negative, rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms . Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in humans, and are occasionally responsible for product recalls...

Spot 42 RNA is 109 nucleotides in length. Its physiological role has remained obscure, but Spot 42 seems to have a regulatory role on the galactose operon. It is proposed that Spot 42 acts by an antisense mechanism where the RNA binds to the galK translation initiator region. Changes in Spot 42 levels are implicated in affecting the adjacent DNA polymerase I levels. The Hfq protein

Hfq protein

The Hfq protein encoded by the hfq gene was discovered in 1968 as an Escherichia. coli host factor that was essential for replication of the bacteriophage Qβ. It is now clear that Hfq is an abundant bacterial RNA binding protein which has many important physiological roles. Usually mediated by...

 has been shown to interact with several small regulatory RNAs in E. coli, and the protein is required for OxyS

OxyS RNA

OxyS RNA is a small non-coding RNA which is induced in response to oxidative stress in Escherichia coli. This RNA acts as a global regulator to activate or repress the expression of as many as 40 genes, by an antisense mechanism, including the fhlA-encoded transcriptional activator and the...

, DsrA

DsrA RNA

DsrA RNA is a non-coding RNA that regulates both transcription, by overcoming transcriptional silencing by the nucleoid-associated H-NS protein, and translation, by promoting efficient translation of the stress sigma factor, RpoS...

, RprA

RprA RNA

The RprA RNA gene encodes a 106 nucleotide regulatory non-coding RNA. Translational regulation of the stationary phase sigma factor RpoS is mediated by the formation of a double-stranded RNA stem-loop structure in the upstream region of the rpoS messenger RNA, occluding the translation initiation...

 and Spot 42 RNA regulation. Transcription of spot 42 is repressed by the CRP

CAMP receptor protein

cAMP receptor protein is a regulatory protein in bacteria. This protein binds cAMP, which causes a conformational change that allows the protein to bind tightly to a specific DNA sequence in the promoters of the genes it controls...

 protein.

Further targets, that have been discovered, imply an extensive role for Spot 42 RNA in catabolite repression

Catabolism

Catabolism is the set of metabolic pathways that break down molecules into smaller units and release energy. In catabolism, large molecules such as polysaccharides, lipids, nucleic acids and proteins are broken down into smaller units such as monosaccharides, fatty acids, nucleotides, and amino...

. Evidence suggests that Spot 42 RNA posttranscriptional positive regulator of gsp

GSP

-People:*Georges St-Pierre, Canadian mixed martial arts fighter*George S. Patton, American military officer*Gregory S. Paul, American freelance paleontologist, author and illustrator-Companies and organizations:*Goodby Silverstein & Partners...

 and dppB and a negative regulator of several genes including fucK

L-Fuculokinase

L-fuculokinase is an enzyme that catalyzes the chemical reactionThus, the two substrates of this enzyme are ATP and L-fuculose, whereas its two products are ADP and L-fuculose-1-phosphate.The gene name used for the gene that encodes L-fuculokinase is fucK....

, galK, fucl and ebgC.