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A M Frischauf

Publications and source records attributed to A M Frischauf.

78 records · Page 5Linked to original sources

Isolation and translation of calvaria procollagen messenger ribonucleic acids.

Procollagen messenger ribonucleic acid (mRNA) was isolated from the calvaria of 15-day-old chick embryos by chromatographing total RNA over oligo(dT)-cellulose two times, and then fractionating the twice-bound RNA on 85% Me2SO/0-20% sucrose gradients. When analyzed on 99% formamide gels, the 27-30S fraction had three sharp fluorescent bands, one corresponding to 27S ribosomal RNA (rRNA), the others having mobilities lower than 27S corresponding to molecular weights of 1 700 000 and 1 800 000. In wheat-germ, cell-free extracts, the 27-30S fraction directed the synthesis of two prominent collagenase sensitive polypeptides with mobilities corresponding to the calvaria pro-alpha chain markers. Twelve percent of this [3H]proline-labeled, wheat-germ product could be hydroxylated with prolyl hydroxylase.

Animals↗

Covalent attachment of DNA to agarose. Improved synthesis and use in affinity chromatography.

DNA has been covalently linked to insoluble matrices of agarose (Sepharose) in high yield using cyanogen bromide activation. Both double-stranded and single-stranded DNA have been coupled with yields up to 225 nmol/mg dry weight Sepharose or 3-8 mumol nucleotide phosphate/ml bed volume. The DNA-Sepharose has been used for (a) the affinity chromatography of various enzymes (Escherichia coli DNA polymerase I and RNA polymerase) from crude extracts or after initial purification steps, resulting in high yields and degrees of purification, and for (b) nucleic acid hybridization. The DNA-Sepharose is stable to high temperature, prolonged storage, and in the case of single-stranded DNA, can be washed with NaOH to destroy nuclease activity and to release any digested oligonucleotides or mononucleotides.

Animals↗

Construction and use of human chromosome jumping libraries from NotI-digested DNA.

A basic difficulty in the molecular analysis of genes identified by mutations in the mammalian genome is the need to cover genetic distances corresponding to several hundred kilobases or more by molecular techniques like chromosome walking. In chromosome jumping, this limitation is overcome by the deletion of all but the extreme ends of large DNA molecules before cloning. We describe here the construction and characterization of a NotI 'jumping library' from human DNA. To characterize this library, random clones were analysed by restriction mapping. Clones carrying unique end fragments were characterized further by hybridization to Southern blots of NotI-cleaved human DNA separated on pulsed field gradient (PFG) gels. As a first step in a directional walk, the library was screened with a clone containing a NotI site cleaved in genomic DNA ('NotI linking clone') localized to the distal third of the short arm of human chromosome 4 (A.-M.F. & T.P., unpublished data). Starting and end points of two identified clones were positioned within a restriction map covering 850 kilobases.

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