Open Access. Powered by Scholars. Published by Universities.®
Immunology and Infectious Disease Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Discipline
Articles 1 - 7 of 7
Full-Text Articles in Immunology and Infectious Disease
Using Rna Interference To Determine The Role Of Varisin In The Innate Immune System Of The Hard Tick Dermacentor Variabilis (Acari: Ixodidae)., Wayne L. Hynes, Martha M. Stokes, Shannon M. Hensley, S. Michelle Todd, Daniel E. Sonenshine
Using Rna Interference To Determine The Role Of Varisin In The Innate Immune System Of The Hard Tick Dermacentor Variabilis (Acari: Ixodidae)., Wayne L. Hynes, Martha M. Stokes, Shannon M. Hensley, S. Michelle Todd, Daniel E. Sonenshine
Biological Sciences Faculty Publications
Defensins are an important component of the innate immune system of ticks. These small peptides are produced by various genera of ticks, and expressed in various tissues. In this study we used RNA interference to silence the expression of the defensin varisin produced by the hemocytes of the American dog tick, Dermacentor variabilis. Ticks were injected with double stranded varisin RNA prior to being placed on a rabbit. After feeding, the ticks were removed, bled, and the hemolymph plasma and hemocytes separated. Hemocytes were screened for the presence (or absence) of both varisin transcript and peptide. Varisin peptide was …
Silencing Expression Of The Defensin, Varisin, In Male Dermacentor Variabilis By Rna Interference Results In Reduced Anaplasma Marginale Infections, Katherine M. Kocan, Jose De La Fuente, Raul Manzano-Roman, Victoria Naranjo, Wayne L. Hynes, Daniel E. Sonenshine
Silencing Expression Of The Defensin, Varisin, In Male Dermacentor Variabilis By Rna Interference Results In Reduced Anaplasma Marginale Infections, Katherine M. Kocan, Jose De La Fuente, Raul Manzano-Roman, Victoria Naranjo, Wayne L. Hynes, Daniel E. Sonenshine
Biological Sciences Faculty Publications
Antimicrobial peptides, including defensins, are components of the innate immune system in ticks that have been shown to provide protection against both gram-negative and gram-positive bacteria. Varisin, one of the defensins identified in Dermacentor variabilis, was shown to be produced primarily in hemocytes but transcript levels were also expressed in midguts and other tick cells. In this research, we studied the role of varisin in the immunity of ticks to the gram-negative cattle pathogen, Anaplasma marginale. Expression of the varisin gene was silenced by RNA interference (RNAi) in which male ticks were injected with varisin dsRNA and then …
Tissue And Life Stage Distribution Of A Defensin-Like Gene In The Lone Star Tick Amblyomma Americanum, S. Michelle Todd, Daniel E. Sonenshine, Wayne L. Hynes
Tissue And Life Stage Distribution Of A Defensin-Like Gene In The Lone Star Tick Amblyomma Americanum, S. Michelle Todd, Daniel E. Sonenshine, Wayne L. Hynes
Biological Sciences Faculty Publications
The transcript sequence of the Amblyomma americanum Linnaeus (Acari: Ixodidae) defensin, termed amercin (amn), was ascertained and a 219-bp amn coding region identified. The gene encodes a 72-amino acid prepropeptide with a putative 37-amino acid mature peptide. This gene shows little similarity to either of the defensins from Amblyomma hebraeum Koch, the only other Amblyomma species for which a defensin has been described. Sequence comparisons with other tick defensins reveal amn to be shorter (6 bp or 2 amino acids) than the Ixodes scapularis Linnaeus (Acari: Ixodidae) and Dermacentor variabilis (Say) (Acari: Ixodidae) defensin sequences. The amercin prepropeptide …
A Defensin-Like Gene Expressed In The Black-Legged Tick, Ixodes Scapularis (Acari: Ixodidae), Wayne L. Hynes, S. M. Ceraul, S. M. Todd, K. C. Seguin, Daniel E. Sonenshine
A Defensin-Like Gene Expressed In The Black-Legged Tick, Ixodes Scapularis (Acari: Ixodidae), Wayne L. Hynes, S. M. Ceraul, S. M. Todd, K. C. Seguin, Daniel E. Sonenshine
Biological Sciences Faculty Publications
The black-legged tick Ixodes scapularis linnaeus (Acari: Ixodidae) is an important vector of microbial pathogens. Knowledge of the tick's innate immune response, particularly defensin and other antimicrobial peptides, is important for understanding how microbes survive in this tick. A defensin gene (slnA) from I. scapularis was obtained by reverse transcription-polymerase chain reaction (RT-PCR) using mRNA extracted from tissues of female ticks. RT-PCR indicated the gene was expressed in the midgut, haemocytes, and fat-body, although no evidence of a peptide was found. Sequencing a cloned cDNA fragment revealed a 225 bp open reading frame encoding a 74 amino acid pre-prodefensin, including …
Defensin In Ticks: Molecular Characterization, Expression, And Role In Innate Immunity, Daniel E. Sonenshine, Wayne L. Hynes, Shane M. Ceraul, Michelle Todd
Defensin In Ticks: Molecular Characterization, Expression, And Role In Innate Immunity, Daniel E. Sonenshine, Wayne L. Hynes, Shane M. Ceraul, Michelle Todd
Biological Sciences Faculty Publications
No abstract provided.
An Arthropod Defensin Expressed By The Hemocytes Of The American Dog Tick, Dermacentor Variabilis (Acari: Ixodidae), Shane M. Ceraul, Daniel E. Sonenshine, Robert E. Ratzlaff, Wayne L. Hynes
An Arthropod Defensin Expressed By The Hemocytes Of The American Dog Tick, Dermacentor Variabilis (Acari: Ixodidae), Shane M. Ceraul, Daniel E. Sonenshine, Robert E. Ratzlaff, Wayne L. Hynes
Biological Sciences Faculty Publications
Both soluble and cell-mediated components are involved in the innate immune response of arthropods. Injection of Borrelia burgdorferi, the Lyme disease agent, results in the secretion of defensin into the hemolymph of the ixodid tick, Dermacentor variabilis. The presence of the peptide is observed as early as 15 min post-challenge and remains present through 18 h post-challenge. As observed in insects and soft ticks, the transcript for defensin is detected as early as 1 h post-challenge in D. variabilis. RT-PCR resulted in an amplicon of 624 bp with a 225 bp region that translates to a 74 …
Identification Of A Defensin From The Hemolymph Of The American Dog Tick, Dermacentor Variabilis, Robert Johns, Daniel E. Sonenshine, Wayne L. Hynes
Identification Of A Defensin From The Hemolymph Of The American Dog Tick, Dermacentor Variabilis, Robert Johns, Daniel E. Sonenshine, Wayne L. Hynes
Biological Sciences Faculty Publications
Hemolymph from partially fed virgin Dermacentor variabilis females was collected following Borrelia burgdorferi challenge and assayed for antimicrobial activity against Bacillus subtilis and B. burgdorferi. A small inducible cationic peptide was identified by SDS-PAGE in the hemolymph of these ticks as early as 1h post challenge. Following purification by a three-step procedure involving sequential SepPak elution, reversed phase high performance liquid chromatography (RP-HPLC) and gel electrophoresis, the yield of the active peptide was approximately 0.1% of the total protein in the hemolymph plasma. The molecular weight, 4.2kDa, was determined by MALDI-TOF mass spectrometry. N-terminal sequencing by the Edman degradation …