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N E Broude

Publications and source records attributed to N E Broude.

53 records · Page 3Linked to original sources

[Primary structure of the alpha subunit of Na+,K+-ATPase. II. Isolation, reverse transcription and cloning of messenger RNA].

Messenger RNA, coding for the alpha-subunit of the Na+, K+-ATPase, was isolated from outer medulla of pig kidney. Within 25S-26S region the mRNA yields a band of specific hybridization with three oligonucleotide probes synthesized according to data on structures of three peptides isolated from the tryptic hydrolysate of the protein. Translation of the enriched poly(A+)-fraction of RNA in Xenopus laevis oocytes followed by the immunochemical identification of the products confirmed the presence of RNA coding for the desired protein. This RNA preparation was used for synthesis and cloning of double stranded cDNA.

Amino Acid Sequence↗

[Problems associated with the use of highly degenerated oligonucleotide probes. Identification of mRNA and cDNA clones corresponding to the gene for the alpha subunit of Na+,K+-ATPase].

Oligonucleotides deduced from the amino acid sequence of a hexapeptide Lys-Asp-Phe-Ala-Glu-Asn were synthesized and used as probes to screen a pig kidney cDNA library for a specific DNA sequence coding for the alpha-subunit of Na+, K+-ATPase. It was shown that the mixed oligoprobe, consisting of 64 heptadecamers, could be only suitable for mRNA blot analysis. To identify the clones with specific cDNA inserts, mixed oligoprobes were fractionated by HPLC technique. For the same purpose a new set of oligonucleotides, synthesized as four groups of 16 different heptadecamers each, was used.

Amino Acid Sequence↗

Proteins of the 30-S subunit of Escherichia coli ribosomes which interact directly with natural mRNA.

Ultraviolet irradiation (254 nm) of the complexes of MS2 phage RNA (mRNA) and the 30-S subunits of Escherichia coli ribosomes prepared at 0 degrees C and 37 degrees C in the presence and absence of initiation factor 3 (IF-3) causes cross-linking of mRNA with proteins S3, S4, S5, S7, S9, S18 and IF-3. Hence, these proteins interact directly with mRNA within the complex 30-S-subunit . mRNA. Addition of IF-3 results in an increase of the rate of complex formation and decrease of its dissociation rate. The addition of IF-3 changes the relative amounts of cross-linked proteins (mainly S3, S4 and S18). Decreasing the temperature from 37 degrees C to 0 degrees C not only decelerates the complex formation rate but also changes the relative amount of cross-linked proteins, indicating the influence of the conditions on the structure of the complex.

Bacterial Proteins↗

Polynucleotide-protein interactions in the translation system. Detection of contacts between some ribosomal split proteins and 16-S RNA in 30-S subunits of Escherichia coli ribosomes.

Direct contacts between 16-S RNA and split proteins S2, S3, S5, S14 and S21 inside the 30-S subunit of Escherichia coli ribosomes were evidenced by the formation of ultraviolet-induced (lambda = 254 nm) RNA-protein cross-links. 30-S subunits were reassembled from core particles and a mixture of split proteins containing in each case a single 125I-labelled protein. All the proteins tested are cross-linked as a result of a single-hit process; proteins S3 and S21 were cross-linked at the highest rate.

Dose-Response Relationship, Radiation↗