week 2 Flashcards
What is the main topic of the lecture?
Protein structure and function
How many genes are present in the human DNA sequence?
About 25,000 genes
What determines the specific proteins produced in different cell types?
Gene activation and RNA transcription
How many different cell types are there in the human body?
200 different cell types
What is the human protein atlas?
The complete set of proteins found in different tissues
What are the primary functions of proteins?
- Biochemical reactions
- Cell shape
- Movement of cells
- Organization of cells
- Manufacturing cellular products
- Waste management
- Receiving signals and executing responses
What are the 20 building blocks of proteins?
Amino acids
What term is used for a sequence of less than 50 amino acids?
Peptide
What is the chemical bond responsible for protein formation?
Peptide bond
What are the four levels of protein structure?
- Primary structure
- Secondary structure
- Tertiary structure
- Quaternary structure
What is the primary structure of a protein?
The sequence of amino acids
What forms the secondary structure of proteins?
Hydrogen bonds
What types of structures can the secondary structure of proteins form?
- Alpha-helix
- Beta-pleated sheet
What defines the tertiary structure of a protein?
Three-dimensional spatial organization and various bonds between side chains
What is a disulfide bond?
Covalent linkages between sulfur groups in cysteine side chains
What is the quaternary structure of a protein?
Multiple polypeptides or protein subunits forming a final active protein structure
What are some common protein modifications?
- Phosphorylation
- Glycosylation
- Ubiquitination
- Acetylation
What is the role of structural proteins?
Maintain internal cell shape and structure
What are the main muscle proteins involved in contraction?
- Actin
- Myosin
What is the most abundant protein in the human body?
Collagen
What is osteogenesis imperfecta?
A disease caused by mutations in collagen type one, resulting in weak bones
What are the three types of cytoskeletal proteins?
- Actin filaments
- Intermediate filaments
- Microtubules
What is the function of histones?
Package DNA into nucleosomes and regulate DNA processes
What do transcription factors do?
Control the process of transcription by binding to specific DNA sequences
What is a common structural feature of many transcription factors?
Zinc finger structure
True or False: Proteins are only involved in structural functions within the cell.
False
