Ribosomal protein S4 from Escherichia coli binds a large domain of 16 S ribosomal RNA and also a pseudoknot structure in the operon mRNA, where it represses its own synthesis. No similarity between the two RNA binding sites has been detected. To find out whether separate protein regions are responsible for rRNA and mRNA recognition, proteins with N-terminal or C-terminal deletions have been overexpressed and purified. Protein-mRNA interactions were detected by (i) a nitrocellulose filter binding assay, (ii) inhibition of primer extension by reverse transcriptase, and (iii) a gel shift assay. Circular dichroism spectra were taken to determine whether the proteins adopted stable secondary structures. From these studies it is concluded that amino acids 48-104 make specific contacts with the mRNA, although residues 105-177 (out of 205) are required to observe the same toeprint pattern as full-length protein and may stabilize a specific portion of the mRNA structure. These results parallel ribosomal RNA binding properties of similar fragments (Conrad, R. C., and Craven, G. R. (1987) Nucleic Acids Res. 15, 10331-10343, and references therein). It appears that the same protein domain is responsible for both mRNA and rRNA binding activities.

CiteULike

Complore

Connotea

Del.icio.us

Digg

Reddit

Technorati

This article has been cited by other articles:

				P. J. Schlax, K. A. Xavier, T. C. Gluick, and D. E. Draper Translational Repression of the Escherichia colialpha Operon mRNA. IMPORTANCE OF AN mRNA CONFORMATIONAL SWITCH AND A TERNARY ENTRAPMENT COMPLEX J. Biol. Chem., October 12, 2001; 276(42): 38494 - 38501. [Abstract] [Full Text] [PDF]

				F. Robert and L. Brakier-Gingras Ribosomal protein S7 from Escherichia coli uses the same determinants to bind 16S ribosomal RNA and its messenger RNA Nucleic Acids Res., February 1, 2001; 29(3): 677 - 682. [Abstract] [Full Text] [PDF]

				P. Korber, T. Zander, D. Herschlag, and J. C.A. Bardwell A New Heat Shock Protein That Binds Nucleic Acids J. Biol. Chem., January 1, 1999; 274(1): 249 - 256. [Abstract] [Full Text] [PDF]

				D. V. Sizova, V. G. Kolupaeva, T. V. Pestova, I. N. Shatsky, and C. U. T. Hellen Specific Interaction of Eukaryotic Translation Initiation Factor 3 with the 5' Nontranslated Regions of Hepatitis C Virus and Classical Swine Fever Virus RNAs J. Virol., June 1, 1998; 72(6): 4775 - 4782. [Abstract] [Full Text] [PDF]

				T. V. Pestova, I. N. Shatsky, S. P. Fletcher, R. J. Jackson, and C. U.T. Hellen A prokaryotic-like mode of cytoplasmic eukaryotic ribosome binding to the initiation codon during internal translation initation of hepatitis C and classical swine fever virus RNAs Genes & Dev., January 1, 1998; 12(1): 67 - 83. [Abstract] [Full Text]