Disease genes and intracellular protein networks

Abstract

By a computational approach we reconstructed genomic transcriptional profiles of 19 different adult human tissues, based on information on activity of 27,924 genes obtained from unbiased UniGene cDNA libraries. In each considered tissue, a small number of genes resulted highly expressed or “tissue specific.” Distribution of gene expression levels in a tissue appears to follow a power law, thus suggesting a correspondence between transcriptional profile and “scale-free” topology of protein networks. The expression of 737 genes involved in Mendelian diseases was analyzed, compared with a large reference set of known human genes. Disease genes resulted significantly more expressed than expected. The possible correspondence of their products to important nodes of intracellular protein network is suggested. Auto-organization of the protein network, its stability in time in the differentiated state, and relationships with the degree of genetic variability at genome level are discussed.

Topology of the Erasmus student mobility network

“…They found that many real-world networks have higher clustering coefficient as it can be obtained from the random graph model of Erdős and Rényi and presented a new model that combines the clustering property and the idea of random connectivity in a graph [5,6]. Their work brought into focus the small-world problem of sociology [7,8] and generated extensive research on various networks [9][10][11][12][13][14][15][16]. As a result, clustering was observed in all types of the investigated graphs and thus became a general characteristic of complex networks.…”

Insights into the Evolutionary Features of Human Neurodegenerative Diseases

“…Proteins with higher interacting partners evolve slower as mutations in protein interaction sites may disrupt the network connectivity affecting the functionality of the proteins [8], [60]–[63]. Hence, considerable lower evolutionary rates of NDD genes in contrast to non-disease genes directed us to scrutinize whether protein connectivity has any influence on their evolutionary rates differences.…”

Protein networks in diseases

“…The expressions were analyzed and compared with reference human genes. Disease genes were more expressed than expected which suggested a possible correspondence of their products to important nodes of intra cellular protein network [9,10]. Pulmonary surfactant proteins and lipids are essential after birth for normal functioning of lungs.…”