Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1998-2-19
pubmed:databankReference
pubmed:abstractText
We have discovered and analysed two novel, linear extrachromosomal double-stranded RNAs (dsRNAs) within oocysts of major north Amercian isolates of Cryptosporidium parvum, a parasitic protozoan that infects the gastrointestinal tract of a variety of mammals, including humans. These dsRNAs were found to reside within the cytoplasm of sporozoites, and were not detected in other species of the genus. cDNAs representing both dsRNA genomes were cloned and sequenced, 1786 and 1374 nt, and each encoded one large open reading frame (ORF). The deduced protein sequence of the larger dsRNA (L-dsRNA) had homology with viral RNA-dependent RNA polymerases (RDRP), with more similarity to polymerases from fungi than those from other protozoa. The deduced protein sequence from the smaller dsRNA (S-dsRNA) had limited similarity with mitogen-activated c-June NH2 terminal protein kinases (JNK) from mammalian cells. Attempts to visually identify or purify virus-like particles associated with the dsRNAs were unsuccessful. Sensitivity of the dsRNAs to RNase A also suggests that the dsRNAs may be unencapsidated. A RDRP activity was identified in crude extracts from C. parvum sporozoites and products of RNA polymerase activity derived in vitro were similar to the dsRNAs purified directly from the parasites.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0950-382X
pubmed:author
pubmed:issnType
Print
pubmed:volume
26
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
289-300
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Virus-like, double-stranded RNAs in the parasitic protozoan Cryptosporidium parvum.
pubmed:affiliation
Division of Biology, Kansas State University, Manhattan 66506, USA. podolsk@ksu.edu
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't