Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.4.21.6 (
thromboplastin
)
13,278
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Two novel serpins with anti-chymotrypsin activity,
RHS
-1 and
RHS
-2, were identified in the tick Rhipicephalus haemaphysaloides. The complementary cDNA sequence of
RHS
-1 was 1286 base pairs (bp) and encoded a deduced 403-amino acid protein with a signal peptide, whereas that of
RHS
-2 was 1682bp and encoded a deduced 380-amino acid protein with no signal peptide. Although both
RHS
-1 and
RHS
-2 exhibited high sequence similarities to known serpins from other ticks, the level of similarity at the amino acid level between the 2 serpins characterized here was only 32.5%. Salivary gland-specific expression of
RHS
-1 and midgut-specific expression of
RHS
-2 were found by Western blot using the relevant antiserum. We tested the ability of purified recombinant rRHS-1 and rRHS-2 to inhibit various serine proteases and found that both significantly inhibited chymotrypsin (95.6% and 94.2%, respectively). We further demonstrated that
RHS
-1, but not
RHS
-2 exhibited anticoagulation activity, based on activated partial
thromboplastin
time (APTT). Disruption of the genes encoding the 2 serpins with RNA interference (RNAi) led to a significant decrease in tick attachment and engorgement rates. These results indicate that
RHS
-1 and
RHS
-2 are 2 novel serpins with anti-chymotrypsin activity that are involved in blood feeding of R. haemaphysaloides.
...
PMID:Isolation and characterization of two novel serpins from the tick Rhipicephalus haemaphysaloides. 2360 11
