Electronic communications and the new biology.
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Biomedical subjects
Publications and source records attributed to D Kristofferson.
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The GenBank nucleotide sequence database now contains sequence data and associated annotation corresponding to 85,000,000 nucleotides in 67,000 entries from a total of 3,000 organisms. The input stream of data coming into the database is primarily as direct submissions from the scientific community on electronic media, with little or no data being keyboarded from the printed page by the databank staff. The data are maintained in a relational database management system and are made available in flatfile form through on-line access, and through various network and off-line computer-readable media. The data are also distributed in relational form through satellite copies at a number of institutions in the U.S. and elsewhere. In addition, GenBank provides the U.S. distribution center for the BIOSCI electronic bulletin board service.
The GenBank nucleotide sequence database now contains sequence data and associated annotation corresponding to 56,000,000 nucleotides in 45,000 entries. The input stream of data coming into the database has largely been shifted to direct submissions from the scientific community on electronic media. The data have been installed in a relational database management system and are made available in this form through on-line access, and through various network and off-line computer-readable media. In addition, GenBank provides the U.S. distribution center for the BIOSCI electronic bulletin board service.
In this paper, we describe an automated system for distributing updates to the GenBank nucleic acid sequence database, using the Usenet news system as the underlying transport mechanism. Our system allows new loci to be distributed as soon as the sequences are available, over existing networks, using existing Usenet software and infrastructure currently available on a wide range of computer systems.
BIONET has made considerable progress in developing communication links among molecular biologists and biochemists worldwide. We describe these efforts and also note the many new enhancements to the BIONET system itself.
Different types of unusual dynamic behavior have been reported for steady-state microtubules. While almost all earlier reports relied on kinetic measurements of bulk polymerization, we have directly visualized the steady-state addition of subunits to individual microtubules through the use of tubulin derivitized with biotin. Biotinylated tubulin was used both as an internal "seed" for polymerization and as a marker for assembly onto the ends of microtubules composed of purified tubulin. Biotinylated segments were distinguished from unmodified tubulin by double-label immunofluorescence. Microtubule lengths, number concentrations, and segment lengths have been monitored with time at steady state under two buffer conditions. The results indicate that the microtubule steady state under these conditions is a balance between a majority of slowly growing microtubules and a minority of rapidly depolymerizing ones as described by the "dynamic instability" model (Mitchison T., and M. Kirschner, 1984, Nature (Lond.)., 312:232-242). Microtubules show no evidence of treadmilling; instead most show progressive growth off both ends at steady state. Although solvent conditions markedly influence the growth rates, qualitatively the behavior is unchanged.