Fou 3 - Organelles Flashcards
Who structure recognize these signals and what happens next?
Nuclear pores recognize these signals and transport proteins into the nucleus via ATPase.
Which are the protein and gene that regulates the cell cycle phases?
Tumor suppressor proteins. Cyclins. Cyclin-dependent kinases.
Which is the Shortest phase of the cell cycle?
M phase.
What are the M phases?
Prophase. Prometaphase. Metaphase. Anaphase. Telophase. And cytokinesis (cytoplasm splits in two).
Which are the tumor suppressor genes?
P53 and RB
What is the function of the tumor suppressor genes?
Normally inhibit G1-to-S progression.
What happes when the tumor suppressor gene is mutated?
Results in unrestrained cell division.
Which are the cancer involved in RB mutation?
Retinoblastoma and Osteosarcoma.
Which is the regulatory protein that activate the CDKs?
Cyclins.
Which is the ubiquitin protein ligase function?
Degraded all the Cyclins, when their cell-cycle specific job is complete. Marks proteins for destruction by ubiquitin protein ligase.
Which proteins bind to and inactivate cyclin-CDK complex?
P21, p27 and p57.
Which protein that inactivate CDKs complexes is controlled by p53?
P53 controls the activation of p21.
Which are the CDKS that the cell needs for progression true the S phase?
Cyclin D/CDK4 and Cyclin E/CDK2.
Which are the CDKS that the cell needs for progression through Mitosis?
Cyclin A/CDK2 (mitotic prophase) and Cyclin B/CDK1(breakdown the nuclear envelop and initiation of mitosis).
What is the Rough Endoplasmic Reticulum function?
It is the site of synthesis of secretory (exported) proteins.
What is the name of the RER in neurons?
Nissl bodies synthesize peptide neurotransmitters for secretion.
Which is the function of Smooth Endoplasmic Reticulum (SER)?
Site of steroid synthesis and detoxification of drugs and poisons.
Which are the places riches in SER?
Liver Hepatocytes, Adrenal cortex and Gonads.
Which are the vesicular trafficking proteins?
COP I, COP II and Clathrin.
What is the function of COP I?
Retrograde Golgi -> Golgi
What is the function of COP II?
Anterograde ER -> cisGolgi
What is the Clathrin’s function?
Trans-Golgi -> Lysosomes; plasma membrane -> endosomes.
What is function of the nuclear localization signals?
Essential component of proteins bound for or residing in the nucleus.
Which is the function of the Golgi apparatus?
Golgi is the distribution center for proteins and lipids from the ER to the vesicles and plasma membrane.
Which are the amino acids that are modified by Golgi apparatus?
Modifies N-oligosaccharides on Asparagine, adds O-oligosaccharides on Serine and Threonine.
What is I-cell disease (inclusion cell disease)?
It is an inherited lysosomal storage disorder; failure of the Golgi to phosphorylate mannose residues, low levels of mannose-6-phosphate.
What is the clinical presentation of the I-cell disease?
Results in coarse facial features, clouded corneas, restricted joint movement, and high plasma levels of lysosomal enzymes.
Hepatosplenomegaly, skeletal abnormalities and may have intellectual disability.
At what age is fatal the I-cell disease?
Death by 8 years.
What is the function of chaperones proteins?
Assist in the folding and transport polypeptides in the ER, Golgi.
Some chaperones are Synthesized constantly.
Which are the Heat shock proteins?
hsp70 and hsp90.
What is the function of the Heat Shock proteins?
These chaperones “rescue” shock stressed proteins from misfolding.
Where does ATP production occurs?
Occurs in mitochondria, TCA cycle and electron transport chain.
What are three roles of mitochondria besides ATP production?
Self-replicating, act as buffer to calcium and role in apoptosis.
Which structure do Beta-oxidation?
Peroxisome.
Which important phospholipid is synthesized by peroxisome?
Plasmalogens is an important phospholipids found in myelin.
Where do we find plasmalogens?
Myelin.
What must be present on a protein in order for that protein to gain entry into the nucleus?
Nuclear localization signal.
Which Cyclin-CDK complexes assist in the progression from G1 phase to S phase?
Cyclin A + CDK2 and Cyclin B + CDK1.
What molecule does the Golgi apparatus add to proteins in order to direct the proteins to the lysosomes?
Mannose-6-phosphate.
What are the three different methods that a cell uses to break down proteins?
Lysosomal degradation. Proteasomal degradation. Calcium-dependent enzymes.
This is the shortest phase in the cell cycle?
M phase.
These two types of protein regulate the transition from one phase of the cell cycle to another?
Cyclins and Cyclins depending kinases.
When RB protein comes unbound from this transcription factor, the cell can prepare to move from G-1 into S phase?
E2F.
