Anti-RCL1 monoclonal antibody Made to order

Ribosome biogenesis in eukaryotes is a highly regulated process involving hundreds of transiently associated proteins and RNAs. Although most of these assembly factors have been genetically linked to specific step(s) in the biogenesis pathway, their biochemical functions are generally unknown. Bms1, an essential protein in yeast, is the only known GTPase required for biosynthesis of the 40S ribosomal subunit and interacts with Rcl1, an essential protein suggested to be an endonuclease. Here, we show thermodynamic coupling in the binding of Bms1 to GTP, Rcl1, and U3 small nucleolar RNA (snoRNA), an essential RNA that base pairs to pre-rRNA. RcI1 binding to preribosomes is severely limited in yeast cells expressing a Bmsl mutant defective for Rcl1 binding. Additionally, we provide evidence that the C-terminal domain of Bmsl acts as an intramolecular GTPase-activating protein. Together, these data suggest that Bmsl functions as a GTP-regulated switch to deliver Rcl1 to preribosomes, providing molecular insight into preribosome assembly.

Fluke burdens, faecal egg output and hepatic damage were assessed in goats immunised with recombinant cathepsin L1 (rCL1) plus Quil A (n = 7) or Quil A alone (control; n = 7) and challenged with Fasciola hepatica. There were no significant differences in fluke burdens (56 +/- 26 vs. 92 +/- 53), average fluke length (20.9 +/- 3.0 vs. 21.0 +/- 3.4 mm) or faecal egg output (525 +/- 533 vs. 758 +/- 677.8 eggs per gram at 17 weeks post-infection) between vaccinated and infected control groups, respectively, but high individual variability was evident. Morphometric and histopathological studies showed reduced hepatic damage in the vaccinated group compared to the infected control, but high individual variability was also recorded. Further vaccine trials in goats should be carried out using a larger number of animals to evaluate rCL1 as a vaccine for fasciolosis in goats. (C) 2009 Elsevier Ltd. All rights reserved.