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This term describes the uncontrolled division of cells due to genetic mutations.
What is cancer?
This type of modification involves attaching a 76–amino acid protein to a target protein to mark it for degradation.
What is ubiquitination?
This type of signaling involves long-distance communication but targets very specific cells rather than widespread distribution like hormones.
What is neuronal signaling?
This cytoskeletal component is the most mechanically durable and is anchored at desmosomes to resist tensile stress.
What are intermediate filaments?
This process explains why proteins with short lifespans, such as regulatory proteins, must be rapidly removed from the cell.
What is regulated proteolysis for cellular control?
These are the two main classes of genes involved in cancer, based on whether mutations are dominant or recessive.
What are oncogenes and tumor suppressor genes?
If ubiquitin tagging fails, this type of cellular damage is likely to accumulate, potentially leading to disease.
What are misfolded or damaged proteins?
A mutation that inhibits this specific activity in Gα would lead to prolonged signaling similar to cholera toxin effects.
What is GTPase activity?
This structural feature of microtubules allows directional transport and is established by α/β-tubulin arrangement.
What is polarity (plus and minus ends)?
A mutation that prevents this activity in Ras keeps it permanently active and promotes cancer.
What is GTP hydrolysis?
This hallmark of cancer allows tumors to stimulate the formation of new blood vessels to supply nutrients.
What is angiogenesis?
A mutation that prevents proteasome function would most directly disrupt this critical cellular process.
What is protein turnover and regulation of protein levels?
This enzyme produces a second messenger that increases more than 20-fold within seconds after GPCR activation.
What is adenylyl cyclase?
Replacing GTP with a non-hydrolyzable analog would cause this specific effect on microtubule dynamics.
What is microtubules would never shrink (loss of dynamic instability)
These two second messengers are produced when phospholipase C cleaves a membrane phospholipid, with one remaining membrane-bound and the other diffusing into the cytosol.
What are DAG and IP₃?
This protein is mutated in about 50% of cancers and is responsible for halting the cell cycle in response to DNA damage.
What is p53?
This is the most likely outcome if ubiquitinated proteins could not enter the proteasome despite being properly tagged.
What is accumulation of tagged proteins leading to cellular dysfunction?
This regulatory mechanism reduces cellular sensitivity to persistent stimulation by decreasing receptor availability through internalization.
What is receptor downregulation?
This motor protein moves toward the minus end of microtubules and would cause cargo accumulation at the axon terminal if nonfunctional.
What is dynein?
This actin filament behavior occurs when monomers add at the plus end and dissociate at the minus end at equal rates.
What is treadmilling?
Loss of function in this tumor suppressor gene is associated with Familial Adenomatous Polyposis (FAP) and early colon tumor development.
What is APC?
The cylindrical structure of the proteasome is important because it performs this protective function for the cell.
What is sequestering proteolysis
This receptor class requires dimerization and autophosphorylation on tyrosine residues to initiate downstream signaling cascades.
What are receptor tyrosine kinases (RTKs)?
This structural unit of muscle contains overlapping actin and myosin filaments and shortens without either filament changing length.
What is a sarcomere?
This calcium-sensitive protein complex shifts tropomyosin to expose myosin-binding sites on actin.
What is troponin?