The evolution scenario and structural variations of Kunitz/BPTI family in the ticks. (A), the evolution scenario of Kunitz/BPTI family in the ticks. Events of different indels (group II type, group III type and other type indels), gene duplication, whole genome duplication, multi-domain and function divergence, occurred during the evolution of Kunitz/BPTI family in the ticks. These events are indicated by different shapes. (B), Structural variations of Kunitz/BPTI family in the ticks. The group II and group III type indels lead to structural changes of Kunitz/BPTI proteins. These changes in structure (group II, group III) relative to classical Kunitz/BPTI proteins (group I) are circled.
Dai et al. BMC Evolutionary Biology 2012 12:4 doi:10.1186/1471-2148-12-4