Cell Cycle Regulators and Cancer Flashcards
22 Questions
100 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What are stimulating proteins?

  • Encoded by suppressor genes
  • Proteins that inhibit cell cycles
  • Encoded by proto-oncogene genes (correct)
  • Proteins that induce apoptosis
  • What are inhibitory proteins?

  • Proteins that stimulate cell cycles
  • Encoded by suppressor genes (correct)
  • Encoded by proto-oncogene genes
  • Proteins that enhance DNA replication
  • How do CDKs become active in cells?

    When they are bound to other proteins called cyclins.

    What happens to the concentration of cyclin in the cell throughout the phases of the cycle?

    <p>The concentration goes up and down depending on the phases of the cycle.</p> Signup and view all the answers

    What are cell cycle regulators?

    <p>Proteins that control the progression of a cell through the cell cycle</p> Signup and view all the answers

    What is the result of improper cell regulation?

    <p>Cancer</p> Signup and view all the answers

    What are growth factors?

    <p>Small proteins that circulate in the bloodstream.</p> Signup and view all the answers

    What is p53 and its purpose?

    <p>It stops progression to S phase by inhibiting the G1 CDK-cyclin complex if the DNA is damaged.</p> Signup and view all the answers

    What are cyclin-dependent kinases (CDKs)?

    <p>The most important cell cycle regulators</p> Signup and view all the answers

    How is anaphase-promoting complex/cyclosome (APC/C) activated?

    <p>When all chromosomes are attached to the mitotic spindle during metaphase.</p> Signup and view all the answers

    How does active APC/C stimulate anaphase?

    <p>Stimulates the destruction of proteins that hold the two copies of each chromosome together at the centromere.</p> Signup and view all the answers

    What kind of proteins inhibit the APC/C?

    <p>Mitotic arrest deficient (MAD) proteins when they are not properly attached to the spindle.</p> Signup and view all the answers

    CDK-cyclin complexes signal the cell to duplicate its DNA.

    <p>True</p> Signup and view all the answers

    Breaks in the two DNA strands during replication activate what protein?

    <p>Ataxia telangiectasia mutated (ATM) protein.</p> Signup and view all the answers

    What is Breast Cancer 1 (BRCA1)?

    <p>It interacts with a series of proteins to mediate either DNA repair or, if the damage is too excessive, cell death.</p> Signup and view all the answers

    What mutations are involved in the development of leukemia and lymphomas?

    <p>Mutations in the ATM gene.</p> Signup and view all the answers

    What mutations are involved in the development of breast and ovarian cancers?

    <p>Mutations in the BRCA1 gene.</p> Signup and view all the answers

    What is the function of retinoblastoma protein (Rb)?

    <p>Prevents cells from entering S phase in the absence of signals from growth factors.</p> Signup and view all the answers

    Mutations that inactivate the tumor suppressor functions of p53 and Rb may lead to cancer or tumor development.

    <p>True</p> Signup and view all the answers

    What are genes that encode p53 and Rb called?

    <p>Tumor suppressor genes.</p> Signup and view all the answers

    If damage to DNA is excessive and cannot be fixed, what happens to the cell?

    <p>The inhibiting protein, p53, can initiate cell death or apoptosis.</p> Signup and view all the answers

    What are kinases?

    <p>Enzymes that add a phosphate to other proteins to activate or inhibit their function.</p> Signup and view all the answers

    Study Notes

    Cell Cycle Regulators

    • Stimulating proteins are encoded by proto-oncogene genes and promote cell growth and division.
    • Inhibitory proteins are encoded by tumor suppressor genes, helping to prevent excessive cell proliferation.

    Cyclins and CDKs

    • Cyclin-dependent kinases (CDKs) require binding to cyclins to become active, facilitating cell cycle progression.
    • Cyclin concentrations fluctuate during the cell cycle, rising and falling in correlation with different phases.

    Cell Cycle Regulation and Cancer

    • Proper cell cycle regulation is critical; any disruption can lead to cancer development.
    • Improper regulation includes mutations in ATM and BRCA1 involved in maintaining DNA integrity, with mutations linked to leukemia, lymphomas, breast, and ovarian cancers.

    Role of Growth Factors

    • Growth factors are small proteins in the bloodstream that signal the rise of G1-phase cyclin concentrations, promoting progression through the cell cycle.

    The Role of p53

    • The p53 protein plays a vital role in DNA damage response, halting progression to the S phase if DNA is damaged, thereby preventing flawed replication.
    • Mutations in p53 can lead to unregulated cell division and tumor formation.

    Anaphase and APC/C

    • The anaphase-promoting complex/cyclosome (APC/C) is activated during metaphase once all chromosomes are properly attached to the spindle, triggering the onset of anaphase.
    • Active APC/C triggers the destruction of cohesion proteins at centromeres, allowing chromatids to separate.

    Inhibition of APC/C

    • Mitotic arrest deficient (MAD) proteins inhibit APC/C when they fail to attach properly to the mitotic spindle, preventing premature anaphase onset.

    Retinoblastoma Protein (Rb)

    • The retinoblastoma protein (Rb) prevents cells from entering the S phase in the absence of growth factor signals, acting as a critical checkpoint.

    Consequences of DNA Damage

    • Breaks in DNA during replication activate the ATM protein, which halts the cell cycle and initiates repair processes.
    • If DNA damage is too extensive and irreparable, p53 can lead the cell to undergo apoptosis to prevent the propagation of damaged DNA.

    Tumor Suppressor Genes

    • Genes encoding p53 and Rb are classified as tumor suppressor genes, essential for regulating cell division and preventing tumor development.

    Kinases and Phosphorylation

    • Kinases are enzymes that add phosphate groups to proteins, modifying their activity (activation or inhibition) through phosphorylation processes.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Description

    Explore key concepts related to cell cycle regulators and their role in cancer through this flashcard quiz. Understand terms like stimulating proteins, inhibitory proteins, and the function of CDKs and cyclins in the cell cycle. Perfect for students learning about cancer biology and cell regulation.

    More Like This

    Cell Cycle Regulators Quiz
    5 questions
    Cell Cycle Regulators Quiz
    18 questions

    Cell Cycle Regulators Quiz

    BestSellingAnemone avatar
    BestSellingAnemone
    Use Quizgecko on...
    Browser
    Browser