Module 8 quiz questions

What can be used to measure cytotoxicity in tissue culture during the screening process?

LDH assay

Which chromatography method relies on charge for separation?

Ion-exchange chromatography

Which chromatography method separates proteins or molecules based on size?

Size exclusion chromatography

Which chromatography method uses specific tags or antibodies to isolate proteins?

Affinity chromatography

When using metal-chelation chromatography, what is used to elute the column and release the bound proteins?

Imidazole

Chemical or UV mutagenesis is particularly useful for studying pathogens that are:

Lacking a complete understanding of their genetics

What is a challenge associated with chemical or UV mutagenesis?

Marking the resulting mutants

What is an advantage of using transposons as genetic tools?

Ability to create a diverse pool of mutants

Why can transposons only be used to study non-essential genes?

Disrupting essential genes can be lethal to the clone

What is an operon?

Multiple genes transcribed into a single RNA molecule

Which reporter gene system generates chemiluminescence for visualization and measurement?

luciferase

What are the limitations of Tn-seq?

Tn-seq cannot identify genes that suppress pathogenesis; Tn-seq can only identify virulence genes that have non-redundant functions; Bias may be introduced due to the competition between mutants in a single animal

What technique allows for the selective inactivation of a gene in specific cells or tissues?

Knockout using Cre recombinase

What is the purpose of using floxed mice in conditional knockout models?

To precisely control gene inactivation in specific cells or tissues

Which type of animal model is commonly used to study the role of neutrophils in immune responses?

Neutropenic mice

What is the main advantage of using laser-capture microdissection (LCM) in studying infections in vivo?

It allows for the isolation of specific cells from tissue sections for analysis

What is the characteristic feature of nude mice?

They lack T cells

What is the main advantage of using "humanized knockin" mice in studying human infections?

They introduce actual human functions into the animal model

What are examples of tools used in gene silencing and editing screens?

RNA interference (RNAi) and gene editing via CRISPER-Cas9

What is the main advantage of proteomics compared to gene and transcript analysis?

Proteomics provides information on protein identity, abundance, sequence, and modifications

Which technique is commonly used to separate protein samples into smaller fractions for proteome coverage?

High-performance liquid chromatography (HPLC)

Which enzyme is responsible for cleaving double-stranded RNA into short interfering RNA (siRNA) in the RNA interference (RNAi) pathway?

Dicer

What is the preferred mechanism for precise gene editing in the CRISPR-Cas9 system?

Homology-directed repair (HDR)

What does CRISPR-Cas9 stand for?

Clustered Regularly Interspaced Short Palindromic Repeats

What is the purpose of RNA interference (RNAi) in studying gene function during infection?

To silence or turn off specific genes