RNase 1 genes from the family Sciuridae define a novel rodent ribonuclease cluster

Journal Article

The RNase A ribonucleases are a complex group of functionally diverse secretory proteins with conserved enzymatic activity. We have identified novel RNase 1 genes from four species of squirrel (order Rodentia, family Sciuridae). Squirrel RNase 1 genes encode typical RNase A ribonucleases, each with eight cysteines, a conserved CKXXNTF signature motif, and a canonical His 12-Lys41-His119 catalytic triad. Two alleles encode Callosciurus prevostii RNase 1, which include a Ser18↔ Pro, analogous to the sequence polymorphisms found among the RNase 1 duplications in the genome of Rattus exulans. Interestingly, although the squirrel RNase 1 genes are closely related to one another (77-95% amino acid sequence identity), the cluster as a whole is distinct and divergent from the clusters including RNase 1 genes from other rodent species. We examined the specific sites at which Sciuridae RNase 1s diverge from Muridae/Cricetidae RNase 1s and determined that the divergent sites are located on the external surface, with complete sparing of the catalytic crevice. The full significance of these findings awaits a more complete understanding of biological role of mammalian RNase 1s. © 2009 US Government.

Full Text

Duke Authors

Cited Authors

  • Siegel, SJ; Percopo, CM; Dyer, KD; Zhao, W; Roth, VL; Mercer, JM; Rosenberg, HF

Published Date

  • 2009

Published In

Volume / Issue

  • 20 / 11-12

Start / End Page

  • 749 - 757

PubMed ID

  • 19771477

International Standard Serial Number (ISSN)

  • 0938-8990

Digital Object Identifier (DOI)

  • 10.1007/s00335-009-9215-4