PubMed · 12701331
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
Albert-László Barabási, Eric Bonabeau. 2003. Scale-free networks.. https://doi.org/10.1038/scientificamerican0503-60
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Viruses can reproduce their progenies only within a host cell, and their actions depend both on its destructive tendencies toward a specific host cell and on environmental conditions. Therefore, knowledge of the subcellular localization of viral proteins in a host cell or virus-infected cell is very useful for in-depth studying of their functions and mechanisms as well as designing antiviral drugs. An analysis on the Swiss-Prot database (version 50.0, released on May 30, 2006) indicates that only 23.5% of viral protein entries are annotated for their subcellular locations in this regard. As for the gene ontology database, the corresponding percentage is 23.8%. Such a gap calls for the development of high throughput tools for timely annotating the localization of viral proteins within host and virus-infected cells. In this article, a predictor called "Virus-PLoc" has been developed that is featured by fusing many basic classifiers with each engineered according to the K-nearest neighbor rule. The overall jackknife success rate obtained by Virus-PLoc in identifying the subcellular compartments of viral proteins was 80% for a benchmark dataset in which none of proteins has more than 25% sequence identity to any other in a same location site. Virus-PLoc will be freely available as a web-server at http://202.120.37.186/bioinf/virus for the public usage. Furthermore, Virus-PLoc has been used to provide large-scale predictions of all viral protein entries in Swiss-Prot database that do not have subcellular location annotations or are annotated as being uncertain. The results thus obtained have been deposited in a downloadable file prepared with Microsoft Excel and named "Tab_Virus-PLoc.xls." This file is available at the same website and will be updated twice a year to include the new entries of viral proteins and reflect the continuous development of Virus-PLoc.
Mitotic and meiotic chromosomes are the compact packages that faithfully transport the genetic and epigenetic information to the following cell generations. How chromatin dynamically cycles between the decompacted interphase state that supports transcription and replication and the compacted state required for chromosome segregation is not understood. To address this long-standing problem, the structure of chromatin should ideally be studied in the physiological context of intact cells and organisms. We discuss here, the contributions that live-cell imaging can and has made to the study of mitotic chromosome compaction and highlight the power and limitations of this approach. We review methodologies used and suggest that combinatorial approaches and developing new imaging technologies will be key to shedding light on this long-standing question in cell biology.
The rates at which cells secrete peptides and proteins must on average equal their rate of synthesis. This basic equality has unanticipated and seemingly categorical negative consequences for the vesicle theory of protein secretion. This is because the transport mechanisms it proposes, such as the budding and fusion of small vesicles and secretion by exocytosis, are not capable of balancing forces. What follows is an account of the analysis that leads to this conclusion.