Ch 1 - 5/2 Dobson Flashcards
SNPs and the causative genetic factor are said to be in what?
Linkage disequilibrium
What type of chromatin is lightly staining, and lightly packed?
Active or inactive?
Euchromatin
Active
Describe heterochromatin
Inactive, dark staining, tightly packed
Which histone is the linker protein?
H1
What type of residues on histones may be phosphorylated for activation or repression?
Serine residues
DNA methylation results in what?
Transcriptional silencing
Describe the process of gene silencing starting with primary miRNA.
Through what mechanisms may gene silencing occur?
Pri-miRNA -> pre-miRNA -> cleaved by DICER -> dsmiRNA -> ssmiRNA which associates with RISC -> target mRNA directs for translational repression or mRNA cleavage
How do lncRNAs modulate gene expression?
Bind chromatin and restrict RNA Pol (XIST) results in gene silencing
What are the 4 ways lncRNAs can affect DNA?
Gene activation
Gene suppression
Promote chromatin methylation and acetylation
Assemble protein complexes
In what cell types is the SER abundant in?
Used for what processes?
Gonads and liver
Steroid hormone and lipoprotein synthesis
Modification of hydrophobic compounds into water-soluble molecules
Which lipid is a marker for apoptosis?
Normally located on what face?
Also serves as what?
Phosphatidylserine
Inner
Cofactors for platelets in blood clotting
What lipid can be phosphorylated and serve as electrostatic scaffold for intracellular proteins?
Can also be what?
phosphatidylinositol
Hydrolyzed by PLC to generate DAG and IP3
What lipids are located on the inner face?
Outer face?
Phosphatidylserine
Phosphtidylethanolamine
Phosphatidylinositol
Phosphatidylcholine
Sphingomyelin / glycolipids
What is responsible for pumping polar compounds (chemotherapeutic drugs) OUT of cells and may render cancer cells resistant to treatment?
MDR protein
If a protein does not contain a signal sequence, where does translation occur?
Free ribosomes in the cytosol
In caveolae-mediated endocytosis noncoated PM invaginations are associated with what?
They are implicated with the regulation of transmembrane signaling via the internalization of what?
GPI-linked molecules, cAMP binding proteins, SRC kinases and the folate receptor
Receptors and Integrins
In muscle cells the protein myosin binds to what? This process is driven by what?
Actin
ATP hydrolysis
Cadherins are associated with what cell-cell interaction?
Integrins?
Desmosomes
Hemidesmosomes
What organelle is responsible for sequestering intracellular calcium?
SER
What process is being described?
Lysosomes fuse with endosomes/phagosomes to facilitate degradation of internalized contents
Heterophagy
What process involves senescent organelles or denatured proteins targeted for lysosomes-drive degradation by encircling them with a double membrane derived from the ER?
Activated by what?
Marked by what protein?
Autophagy
cell stressors
LC3 protein
What kind of proteins may go though the proteasome degradation pathway?
Cytosolic (TFs or regulatory)
Senescent
Denatured
High levels of misfolded proteins within the ER triggers what?
Leads to what?
Unfolded protein response
Reduction in protein synthesis and increase in chaperone proteins to aid in refolding
How do mitochondria initiate protein synthesis, with what?
N-formylMethionine
What is it called when rapidly growing cells upregulate glucose and glutamine uptake but decrease their production of ATP per glucose molecule?
Warburg effect
Wnt binds Frizzled and regulates intracellular levels of what?
The stabilized pool is able to do what?
Beta-catenin
Translocate to the nucleus and form a transcriptional complex
Signaling from a Tyr kinase-based receptor involves the activation of RAS via GTP binding. What 2 downstream effects does RAS have?
(Give the both whole pathways)
Activates RAF -> MAPK -> activates transcription w/MYC protein and there is cell cycle progression
Or
activates PI3K -> Akt -> mTOR -> activates transcription in same way
Which growth factor comes from mesenchymal cells?
VEGF
Which growth factor enhances proliferation of hepatocytes and other epithelial cells, increases cell motility?
HGF (scatter factor)
Which growth factor stimulates keratinocyte migration, proliferation, and differentiation?
Comes from where?
KGF (FGF-7)
Fibroblasts
Which growth factor stimulates proliferation of endothelial cells and increases vascular permeability?
VEGF
Which growth factor is chemotactic for neutrophils, macrophages, smooth muscle cells, fibroblasts and stimulates proliferation of fibroblasts, endothelial cells, and stimulates ECM protein synthesis?
PDGF
Which growth factor is chemotactic for leukocytes and fibroblasts, stimulates ECM protein synthesis, and suppresses acute inflammation?
TGF-B
Which growth factor is chemotactic and mitogenic for fibroblasts, stimulates angiogenesis and ECM protein synthesis?
FGFs
Which growth factor is mitogenic for keratinocytes and fibroblasts, stimulates keratinocyte migration, and stimulates formation of granulation tissue?
EGF
Which FGF is basic?
Acidic?
FGF-2
FGF-1
Which growth factor stimulates proliferation of hepatocytes and other epithelial cells?
TGF-alpha
What receptor associated with EGF is overexpressed in breast cancers?
ERBB2 (HER2)
What is the most important inducer of VEGF?
Hypoxia via HIF-1
PDGF and TGF-a also are inducers
What is the major angiogenic factor after injury and in tumors?
VEGF-A
What are the fibrous structural proteins?
What do they confer?
Cross linked by what?
Collagens and elastin
Tensile strength and recoil
Lysyl oxidase
Lysyl oxidase requires what?
Without it there what will result?
Vitamin C
Easy bleeding and poor healing
Elastins are important in what structures?
Cardiac and large blood vessels
What kind of defects lead to weakened aortic walls?
What associated syndrome?
Fibrillin
Marfan syndrome
What forms highly compressible gels that confer resistance to compressive forces and provides lubrication in joint cartilages?
Proteoglycans and hyaluronan
What makes up the basement membrane?
Type 4 collagen
Laminin
What makes up the interstitial matrix?
Fibronectin
Elastin
Proteoglycans
Hyaluronate
Which CDKIs inhibit all CDKs?
p21, p27, p57
What is the G1 to S regulator?
What is monitored here?
E-CDK2
D-CDK4 and D-CDK6
Integrity of the DNA
What INK4 inhibitors will act on D-CDK4 and D-CDK6?
p15, p16, p18, p19
The S phase requires what cyclins and cdk’s to be active?
A-CDK2 and A-CDK1
The G2 to M transition requires what cyclin/cdk?
B-CDK1
What type of DNA variation is bi-allelic, involves gene-coding sequences and may be responsible for phenotypic differences?
CNV (copy # variation)