Tick salivary platelet aggregation inhibitor that plays an important part in the anti-hemostatic strategy of ticks. Inhibits platelet aggregation induced by ADP (IC(50)~150 nM), collagen, and platelet activating factor (PAF) (PubMed:18070663). Acts by binding to platelet membrane glycoprotein IIb-IIIa (ITGA2B/ITGB3) in a metal ion dependent manner (PubMed:18070663). Does not inhibit aggregation induced by ristocecin, an agonist that aggregates platelets independently from the glycoprotein IIb-IIIa (ITGA2B/ITGB3). In contrast to other tick platelet aggregation inhibitors, this protein does not protect ITGA2B/ITGB3 from dissociation under SDS condition, suggesting it may dissocate much faster than its orthologs (PubMed:18070663). Expressed in salivary glands. The N-terminus is blocked. The monogrins comprise about 4% of the total salivary gland protein.