Exploring Helicobacter pylori virulence gene expression via small RNA analysis
Faculty Mentor
Andrea Castillo
Presentation Type
Poster
Start Date
4-14-2026 11:30 AM
End Date
4-14-2026 1:30 PM
Location
PUB NCR
Primary Discipline of Presentation
Biology
Abstract
Helicobacter pylori is a bacteria that infects human gastric epithelial cells in over half the global population. Infections are usually asymptomatic, but symptomatic disease can include gastritis, peptic ulcer disease, cancers, or other conditions. Virulence factors are pathogen characteristics associated with occurrence of disease and its severity. Major H. pylori virulence factors are encoded by the cytotoxin-associated gene pathogenicity island (cagPAI) region of the chromosome. They include a Type IV secretion system (T4SS) and the CagA protein. The T4SS is a syringe-like protein structure that translocates CagA into host gastric epithelial cells. Once inside, CagA interferes with host cell signaling and morphology. Although much is known about how T4SS translocates CagA into host cells, relatively little is known about how cagPAI gene expression is regulated. Since there are few protein regulators, riboregulation, a form of regulation that employs small RNAs (sRNAs), is suspected to play a large role here. Previous experiments in our lab suggest that H. pylori sRNAs, sRNA-HPnc2540 and sRNA-HPnc2620, regulate expression of the cagPAI genes. Before this data is published, the genomic location and size of both sRNAs must be confirmed. To confirm the genomic location, a reverse transcription and primer walking strategy and Northern blot will be used. RNA extracted from wildtype H. pylori was cleaned to remove contaminating genomic DNA, then converted into cDNA. Polyermase chain reaction (PCR) with various oligo combinations will be used to identify the 5’ and 3’ ends of the sRNA-HPnc2540 and sRNA-HPnc2620 transcripts. For the Northern blot, extracted RNA will be resolved on a polyacrylamide gel, blotted to a membrane, and probed with a fluorescently labeled oligo complimentary to a known region of each sRNA. Comparison of a fluorescing band on the blot to a set of markers will reveal the sRNA length. The size, in conjunction with the confirmed 5’ end of the gene, will establish each sRNA’s genomic location.
Recommended Citation
Strong, Caitlyn, "Exploring Helicobacter pylori virulence gene expression via small RNA analysis" (2026). 2026 Symposium. 26.
https://dc.ewu.edu/srcw_2026/ps_2026/p2_2026/26
Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.
Exploring Helicobacter pylori virulence gene expression via small RNA analysis
PUB NCR
Helicobacter pylori is a bacteria that infects human gastric epithelial cells in over half the global population. Infections are usually asymptomatic, but symptomatic disease can include gastritis, peptic ulcer disease, cancers, or other conditions. Virulence factors are pathogen characteristics associated with occurrence of disease and its severity. Major H. pylori virulence factors are encoded by the cytotoxin-associated gene pathogenicity island (cagPAI) region of the chromosome. They include a Type IV secretion system (T4SS) and the CagA protein. The T4SS is a syringe-like protein structure that translocates CagA into host gastric epithelial cells. Once inside, CagA interferes with host cell signaling and morphology. Although much is known about how T4SS translocates CagA into host cells, relatively little is known about how cagPAI gene expression is regulated. Since there are few protein regulators, riboregulation, a form of regulation that employs small RNAs (sRNAs), is suspected to play a large role here. Previous experiments in our lab suggest that H. pylori sRNAs, sRNA-HPnc2540 and sRNA-HPnc2620, regulate expression of the cagPAI genes. Before this data is published, the genomic location and size of both sRNAs must be confirmed. To confirm the genomic location, a reverse transcription and primer walking strategy and Northern blot will be used. RNA extracted from wildtype H. pylori was cleaned to remove contaminating genomic DNA, then converted into cDNA. Polyermase chain reaction (PCR) with various oligo combinations will be used to identify the 5’ and 3’ ends of the sRNA-HPnc2540 and sRNA-HPnc2620 transcripts. For the Northern blot, extracted RNA will be resolved on a polyacrylamide gel, blotted to a membrane, and probed with a fluorescently labeled oligo complimentary to a known region of each sRNA. Comparison of a fluorescing band on the blot to a set of markers will reveal the sRNA length. The size, in conjunction with the confirmed 5’ end of the gene, will establish each sRNA’s genomic location.
