MRNA transcription

Campus Updates and Testing Procedures

Issues with exam registration due to reduced testing centers.
Emphasis on the importance of completing exams without grade penalties for circumstances beyond students' control.
Adjustments to deadlines for pre-class quizzes due to water main break complications.

Urges students to keep up with assignments despite disruptions.
Plan to push deadlines to Friday but stresses the need to continue submitting work.
Reminder about completing exams as a priority with support for those struggling to register.

Definition of vaccines: substances that help the immune system recognize and fight off diseases without causing the disease itself.
Immunological process: vaccines stimulate immune response, creating memory cells that produce antibodies.
- Description of how dead or weakened pathogens are used.
Types of vaccines:
- Inactivated vaccines: contain dead viruses (e.g., polio, rabies, hepatitis A).
- Live attenuated vaccines: contain weakened pathogens (e.g., MMR: measles, mumps, rubella).
- Subunit, recombinant, or conjugate vaccines: use components of pathogens, like inactivated toxins (e.g., tetanus, diphtheria).

Immune cells, such as phagocytes, engulf and break down pathogens during the exposure to the vaccine.
Memory cells are formed after initial immune response, which facilitates quicker responses in future exposures to the same pathogen.
Primary immune response timeline:
- Initial activation: ~two weeks to identify and respond to the pathogen.
- Secondary activation: more rapid response (hours to days) due to memory cells.

Basic components of viruses: proteins and nucleic acids (DNA or RNA).
Role of nucleic acids in viral replication and protein synthesis using the host's cellular machinery.
Importance of spike proteins in viral entry into host cells.

Concept of mRNA vaccines:
- Utilize a piece of the virus's mRNA to instruct the host cell to produce viral proteins, which triggers an immune response.
Explanation of the immune response mechanism:
- Vaccine mRNA is transcribed into proteins that elicit antibody production against the virus.
Benefit of mRNA vaccines:
- mRNA has a short half-life, ensuring it does not persist in the body after the immune response is triggered.

Discussion of mild side effects following vaccinations:
- Common response due to inflammation as the body mounts an immune defense.
- Comparisons made to feeling symptoms after a physical injury and how inflammation is part of the body's healing process.
Clarification that vaccination responses should not be as severe as natural infection.

Dr. Katalin Karikó's contributions over decades leading to the development of mRNA technology for vaccines.
Other key figures in mRNA vaccine development for COVID-19:
- Dr. Drew Weissman, Dr. Barney Graham (Moderna).
Rapid vaccine development facilitated by pre-established research and funding.

Presentation of data from Pfizer's clinical trials showing significant drop in COVID-19 cases post-vaccination compared to placebo.
Clarification on how vaccines do not provide absolute immunity but enhance body's ability to respond to infections more effectively.

The distinction between DNA in various cell types despite having the same genetic material:
- Gene expression differences lead to the production of different proteins in distinct cell types.
Explanation of the concept of differentiation in embryonic development.
Activity planned focusing on gene regulation using examples from stickleback fish genetics.

Overview of transcription process:
- DNA serves as a template for RNA polymerase to produce mRNA.
- Key differences between RNA and DNA discussed:
- RNA uses uracil (U) in place of thymine (T), and has ribose sugar instead of deoxyribose.
- RNA is typically single-stranded, while DNA is double-stranded, providing stability.