Differential expression of genes in uninfected and rickettsia-infected Dermacentor variabilis ticks as assessed by differential-display PCR.
Ticks serve as both the vector and the reservoir for members of the spotted fever group rickettsiae. The molecular interaction(s) that results from this close relationship is largely unknown. To identify genetic factors associated with the tick response to rickettsial infection, we utilized differential-display PCR. The majority of upregulation appeared in the infected tissue. We cloned and sequenced 54 differentially expressed transcripts and compared the sequences to those in the GenBank database. Nine of the 54 clones were assigned putative identities and included a clathrin-coated vesicle ATPase, peroxisomal farnesylated protein, Ena/vasodilator-stimulated phosphoprotein-like protein, alpha-catenin, tubulin alpha-chain, copper-transporting ATPase, salivary gland protein SGS-3 precursor, glycine-rich protein, and Dreg-2 protein. Confirmation of the rickettsial influence on the differential expression in the ovaries for a number of these clones was demonstrated by semiquantitative reverse transcription-PCR and Northern blot analyses, resulting in confirmation of six out of nine and three out of four assessed clones, respectively. Further characterization of the clones identified tissue-dependent expression in the midguts and salivary glands. The potential roles of these molecules in the maintenance and transmission of rickettsiae are discussed.
Department of Microbiology and Immunology, School of Medicine, University of Maryland, Baltimore, Baltimore, Maryland 21201, USA. kmaca001@umaryland.edu
Kevin R
KR
Macaluso
Albert
A
Mulenga
Jason A
JA
Simser
Abdu F
AF
Azad
D000818:Animals; D015152:Blotting, Northern; D003598:Cytoskeletal Proteins / Q000032:analysis; D003870:Dermacentor / Q000235:genetics* / Q000821:virology*; D005260:Female; D020869:Gene Expression Profiling; D007413:Intestinal Mucosa / Q000378:metabolism; D010053:Ovary / Q000378:metabolism; D016133:Polymerase Chain Reaction / Q000379:methods*; D012281:Rickettsia / Q000472:pathogenicity*; D012282:Rickettsia Infections / Q000635:transmission*; D012469:Salivary Glands / Q000378:metabolism; D025262:Vacuolar Proton-Translocating ATPases / Q000378:metabolism; D051178:alpha Catenin
D003598:Cytoskeletal Proteins; D051178:alpha Catenin; D025262:Vacuolar Proton-Translocating ATPases