Network research of aging with focus on biological network alignment

 

Organizing committee

Tijana Milenkovic, Department of Computer Science and Engineering, University of Notre Dame, Contact: tmilenko [at] nd [dot] edu
Fazle E. Faisal, Department of Computer Science and Engineering, University of Notre Dame, Contact: ffaisal [at] nd [dot] edu

Meeting date, time, and place

September 20, 4:30-6:30pm, Baycliff Room.

Tutorial summary

Genes (proteins) interact with each other to keep us alive. And this is exactly what biological networks model. Therefore, biological network research is promising to revolutionize our biological understanding.

Because susceptibility to diseases increases with age, studying human aging is important. But studying human aging experimentally is hard. Hence, aging-related knowledge needs to be transferred from model species. This transfer has traditionally been carried out by genomic sequence alignment. But because sequence data and biological network data can give complementary insights, sequence alignment alone can limit the knowledge transfer. Thus, biological network alignment can be used to transfer aging-related knowledge between topologically and functionally conserved network regions of different species.

Gene expression research has also been indispensable for investigating aging, but it typically ignores genes' interconnectivities. Thus, analyzing genes' topologies in biological networks could contribute to our understanding of aging. However, current methods for analyzing systems-level biological networks deal with their static representations, although cells are dynamic. Because of this, and because different data can give complementary biological insights, current static biological networks can be integrated with aging-related expression data to form dynamic, age-specific biological networks. Then, cellular changes with age can be studied from such biological networks.

With the above motivation in mind, this tutorial will review state-of-the-art biological network research of aging. The tutorial is designed at the introductory level, giving enough background on the proposed topics. It is intended to bring together scientists at all stages of their career with interests or expertise in computational or mathematical analyses of biological networks, or in applications of the methods to practical problems in biology, such as aging, evolution, disease, or therapeutics.

Tutorial description

As more biological network data is becoming available owing to advances in high-throughput biotechnologies for interactome detection, meaningful alignments of biological networks of different species could be viewed as one of the foremost problems in computational biology. Since network alignment aims to find regions of similarities between biological networks of different species, it could guide the transfer of biological knowledge across species between conserved network regions. This is important since many nodes in biological networks are currently functionally uncharacterized even for well-studied model species. In particular, this is important when studying human aging: since human aging is hard to study experimentally due to long lifespan as well as ethical constraints, the knowledge about aging needs to be transferred from model species. Traditionally, the transfer of biological knowledge between species has been restricted to genomic sequence alignment. However, since biological networks and sequences can give complementary biological insights, indicating that biological network data can elucidate function that cannot be extracted from sequence data by current methods, restricting alignment to sequences may limit the knowledge transfer.

Since susceptibility to diseases increases with age, studying molecular causes of aging gains importance. Hence, after discussing in depth (dis)advantages of existing network alignment methods, the tutorial will demonstrate how the methods can be used to infer network-based functional orthologs and transfer aging-related knowledge from well annotated model species to poorly annotated human. That is, the use of network alignment in deepening our current knowledge about (human) aging will be discussed.

In addition to network alignment, the tutorial will introduce alternative network-based computational strategies for studying aging. Namely, it will show how integrating current static biological network data with aging-related gene expression data to construct age-specific networks and then dynamically studying these networks provides a valuable model of cellular functioning that can reveal novel key players in aging, and that can reveal more of the novel aging-related information than static network analysis of individual biological data types, as has traditionally been done in the field of biological network research.

Topics

  1. Introduction to network alignment
  2. Focus on different global network aligners
  3. Using comparative network analysis to reveal key players in aging
  4. Using dynamic network analysis to reveal key players in aging