Evolution of Vertebrate Hemostatic and Inflammatory Control Mechanisms in Blood-Feeding Arthropods

Arthropods evolved blood-feeding lifestyles on more than 20 independent occasions. A comparison of sialomes (secretory salivary gland protein family repertoires) corroborates this and indicates that unique protein families are found for different blood-feeding lineages. Closely related lineages considered to have evolved blood-feeding behavior independently might share similar sets of protein families in their sialomes. No orthologous relationships or conserved functional mechanisms have, however, been found for these apparently related protein family members. This implies that sialomes were already defined before the divergence of these related lineages, but that the functions involved in blood feeding evolved at a later stage. Protein families prone to lineage-specific expansion (gene duplication) tend to be abundant with specialized functions associated with various gene duplicates. A central theme that seems to emerge from comparative sialomic analysis is that of the convergent evolution of modulatory strategies that targets host defenses even if the molecular mechanisms differ. Copyright © 2010 S. Karger AG, Basel Received: September 1, 2010 Accepted after revision: September 30, 2010 Published online: October 28, 2010 Journal of Innate Immunity Dr. Ben J. Mans Agricultural Research Council-Onderstepoort Veterinary Institute Parasites, Vectors and Vector-Borne Diseases, Old Main Building Onderstepoort 0110 (South Africa) Tel. +27 12 529 9200 or +27 12 529 9434, E-Mail mansb @ arc.agric.za © 2010 S. Karger AG, Basel 1662–811X/11/0031–0041$38.00/0 Accessible online at: www.karger.com/jin D ow nl oa de d by : 54 .7 0. 40 .1 1 11 /2 3/ 20 17 2 :4 4: 24 A M