TashHN, a Theileria annulata encoded protein transported to the host nucleus displays an association with attenuation of parasite differentiation.
The intracellular apicomplexan parasite, Theileria annulata, manipulates its bovine host cell by over-riding the cells natural apoptotic response and inducing proliferation of the infected leukocyte. We have recently identified a T. annulata encoded family of polypeptides (TashATs) with characteristics that indicate that they are involved in control of host cell gene expression. Here we present data on another member of this family, TashHN, showing that it is located to the parasite and host cell nucleus. Immunoblot analysis demonstrated that, unlike TashAT2 and 3, TashHN displays three forms, the largest of which is enriched in the host nuclear fraction and appears to be phosphorylated. Northern and 5 prime race analyses identified multiple TashHN RNA species in infected cells that have retained the ability to differentiate. These transcripts showed subtly different kinetics, but all decreased during differentiation to the merozite, and two showed reduced levels prior to down-regulation of the other TashATs. In addition, analyses of multiple cell lines that have become severely attenuated in their potential to differentiate, indicated a substantial increase in TashHN expression, with host nuclear reactivity particularly enhanced.
Swan
David G
DG
Department of Veterinary Parasitology, University of Glasgow, Bearsden Road, Glasgow, G61 1QH, UK.
Stadler
Laura
L
Okan
Emel
E
Hoffs
Michael
M
Katzer
Frank
F
Kinnaird
Jane
J
McKellar
Sue
S
Shiels
Brian R
BR
D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism*; D025461:Feedback, Physiological; D005786:Gene Expression Regulation; D008969:Molecular Sequence Data; D009024:Morphogenesis; D021382:Protein Sorting Signals; D021381:Protein Transport; D015800:Protozoan Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016053:RNA, Protozoan / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D016796:Theileria annulata / Q000235:genetics / Q000254:growth & development / Q000378:metabolism* / Q000472:pathogenicity*
D021382:Protein Sorting Signals; D015800:Protozoan Proteins; D012333:RNA, Messenger; D016053:RNA, Protozoan; D011993:Recombinant Fusion Proteins