Life Sciences Commons^™

Mapping Adenines, Guanines, And Pyrimidines In Rna, Helen Donis-Keller, Allan Maxam, Walter Gilbert

Helen Donis-Keller

The positions of adenines, guanines, and pyrimidines can be determined by partial nuclease digestion of a terminally labeled RNA molecule. In urea, at elevated temperatures, RNase T1 generates a pattern reflecting cleavage at guanines while RNase U2 cleaves only at adenine. A limited alkaline hydrolysis provides a continuum of fragments derived from breaks at every phosphodiester bond. The reaction products are electrophoretically fractionated by size in adjacent lanes of a polyacrylamide gel. An autoradiograph of the gel displays the sequence up to 100 nucleotides from the end of the molecule, although uracil cannot as yet be distinguished from cytosine. These …

Separation Of Quantitation Of Intracellular Forms Of Poliovirus Rna By Agarose Gel Electrophoresis, Martinez Hewlett, Shmuel Rozenblatt, Victor Ambros, David Baltimore

Victor R. Ambros

Intracellular poliovirus-specific RNA species can be measured directly by electrophoresis of total cytoplasmic nucleic acids through 1% agarose gels, resulting in the separation of single- and double-stranded forms of poliovirus RNA from each other and from HeLa cell 28S ribosomal RNA. Single-stranded RNA molecules differing by only 15% in length are resolved in this gel system. RNA species can be visualized as fluorescen bands appearing after staining of the gels with ethidium bromide and observation under ultraviolet illumination. The total amount of RNA can be determined by densitometric quantitation of the fluorescent response. In this way, the amount of poliovirus-specific …

Covalent Linkage Of A Protein To A Defined Nucleotide Sequence At The 5'-Terminus Of Virion And Replicative Intermediate Rnas Of Poliovirus, James B. Flanegan, Ralf F. Pettersson, Victor R. Ambros, Martinez J. Hewlett, David Baltimore

Victor R. Ambros

The 5'-terminus of poliovirus polyribosomal RNA is pUp. A candidate for the 5'-terminus of poliovirion RNA was recovered as a compound migrating toward the cathode when 32P-labeled virion RNA was completely digested with ribonucleases T1, T2 and A and analyzed by paper ionophoresis at pH 3.5. Treatment with proteinase K reversed its direction of migration, indicating the presence of protein. Treatment with venom phosphodiesterase liberated all of the radioactivity as pUp, suggesting that poliovirion RNA has a protein-pUp 5'-terminus. Treatment of virion RNA with T1 ribonuclease alone generated a proteinase K-sensitive oligoribonucleotide. Analysis of the oligoribonucleotide using ribonucleases A and …

Algae-Grazer Interactions, Warren Abrahamson

Warren G. Abrahamson, II

No abstract provided.

Solidago Canadensis Galls: A Study Of Interacting Natural Populations, Warren Abrahamson

Warren G. Abrahamson, II

No abstract provided.

Niche Analysis Of Marine Algae, Warren Abrahamson

Warren G. Abrahamson, II

No abstract provided.

The Effects Of Grazing On Vegetation, Warren Abrahamson

Warren G. Abrahamson, II

No abstract provided.

Mosquito Diversity In St. Joseph County, Indiana (Diptera: Culicidae)., Donald Shroyer, Raymond Beach, Leonard Munstermann, John Peloquin, John Petersen, Richard Smith, David Taylor

David B. Taylor

An intensive mosquito survey of St. Joseph County, Indiana, was undertaken in 1976 to provide information on mosquito diversity, distribution, and abundance within the area. Location of larval breeding sites was emphasized, supplemented by a New Jersey light-trap program and man-bait collections. Over 2000 larval sites were identified in the 500 square-mile area.

Of the 52 species of mosquito known to occur in Indiana, 35 (8 genera) are endemic to St. Joseph County. Larval sites for most species were identified within the county, and 31 species were represented in the light-trap collections.