Cistrons

Altus Biologies. Cistron Biotechnology, Inc. Matrix Pharmaceutical. Scios... 

McGraw DW, Forbes SL, Kramer LA, Liggett SB. Polymorphisms of the 5 leader cistron of the human beta2-adre-nergic receptor regulate receptor expression. J Clin Invest 1998 102 1927-1932. 

In our work, we opted to deploy the IRES sequences within the 5 UTR of mono-cistronic reporter mRNA (Humphreys el al, 2005 Fig. 6.IB), which were directly transfected into HeLa cells. IRES-containing transcripts were further capped with the nonphysiological A(5/)ppp(5/)G cap structure,... 

We use the plasmid pSP/CAT cut with the enzyme Pvu II as template for in vitro transcriptions. This produces an mRNA that is approximately 150 nucleotides in length (Gorman, 1985). For the HCV IRES, we use the plasmid phRL-null, in which the HCV IRES has been cloned into the Nhe I site, upstream of the renilla cistron (Robert el al., 2006b). In vitro transcriptions are performed as described previously, except that 5 fiCi oc32P-GTP replaces 3H-CTP in the reaction to label the mRNA. 

Andrews, S. C., Berks, B. C., McClay, J., Ambler, A., Quail, M. A., Golby, P. and Guest, J. R. (1997) A 12-cistron Escherichia coli operon (hyf) encoding a putative proton- translocating formate hydrogenlyase system. Microbiology, 143, 3633-47. 

McGraw DW, Liggett SB. (1999) Coding block and 5 leader cistron polymorphisms of the beta2-adrenergic receptor. Clin Exp Allergy. 29(suppl. 4), 43-45. 

Parola AL, Kobilka BK. (1994) The peptide product of a 5 leader cistron in the beta 2 adrenergic receptor mRNA inhibits receptor synthesis. J Biol Chem. 269, 4497-4505. 

A stretch of DNA that is transcribed as a single continuous RNA strand is called a transcription unit. A unit of transcription may contain one or more sequences encoding different polypeptide chains (translational open reading frames, ORF) or cistrons. The transcription unit is sometimes termed the primary transcript, pre-messenger RNA or heterogeneous nuclear RNA (hnRNA). The primary transcript is further processed to produce mRNA in a form that is relatively stable and readily participates in translation. In order to understand the primary need for processing of this RNA, the biochemical definition of a gene must be discussed. 

Cistron. A genetic unit that encodes a single polypeptide chain. 

Polycistronic messenger RNA. In prokaryotes, an RNA that contains two or more cistrons note that only in prokaryotic mRNAs can more than one cis-tron be utilized by the translation system to generate individual proteins. 

The F-type H+-ATPase (FoFi) of E coli is coded by unc (alp) operon. Following a mutation in any one of the eight cistrons, the enzyme becomes defective in ATP synthesis and the bacteria are unable to grow on succinate as the sole carbon source.4-8 The E coli FoFi has been purified in the presence of detergents by combined column chromatographies or a series of density gradient centrifugations.2 31 ... 

The polycistronic structure of prokaryotic mRNA presents another intriguing prospect. In some cases, a downstream cistron lacking a strong (or exposed) RBS is... 

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