Introduction to Path Flashcards
HAT vs. HDAC proteins
HAT (histone acetyl transferase): opens up chromatin to allow gene translocation (euchromatin)
HDAC: removes acetyl group causing histone to close up chromatin (heterochromatin), which prevents gene translocation.
Types and function of Non-coding mRNA
miRNA: used in post translational silencing
lncRNA: modulate gene expression, ie XIST gene, which turns off X chromosome making Barr body.
Phosphatidylinositol
Found on the inner membrane
Used for protein scaffolding for intracellular proteins
PLC can break it down to make IP3 and DAG
Phosphatidylserine
Found in the inner membrane
If it is on the outer membrane it becomes a cell marker for phagocytosis.
Cofactor for platelet activation
Cancer type if … is found in high concentration
Lamin A, B, and C Vimentin Desmin Neurofiliments Glial fibrillary acidic protein
Lamin=nuclear lamina in calls
Vimentin= mesenchymal cells (fibroblasts/endothelium)
Desmin: skeletal muscle
Neurofiliments: Axons of neurons
Glial fibrillary acidic protein: glial cells around neurons.
Progeria
When a person gets premature old age because of a lamin mutation
Dynein vs. Kinesin
Dynein: retrograde transportation (to nucleus)
Kinesin: anterograde transport (away from nucleus)
Cystic Fibrosis
CFTR defect: chloride channel defect
Protein can’t fold properly, can trigger ER stress response
I-cell disease
Golgi is unable to put Mannose 6 phosphate on the vesicle, so the enzymes can’t be sent to the lysosome.
Patient will die due to lack of function of white blood cells.
Warburg effect
Increased uptake of glucose and glutamine in cells but a decreased net ATP made per glucose molecule break down because carbon units being diverted to cell division prerequisites (HMP shunt pathway).
This happens in normal cells in G1/G2 phase and in cancer cells.
Necrosis
Cell death by disruption of the mitochondria.
The mitochondria leaks into the cell causing a drop in the pH, which leads to cell death.
Apoptosis
Programed cell death, which can be caused by
Cytochrome C release (inhibition of BLC-2)
Receptor Type for insulin
RTK
Growth factors likeEGF, PDGF, TGF… use which receptor type?
RTK
HER2 mutation (ERBB mutation)
Leads to breast cancer
HGF (scatter factor)
Mitogenic effects on hepatocytes, epithelial cells, biliary, pulmonary, renal, mammillary, and epidermal cells.
Plays a huge role in development and cell migration
Produced by mesenchymal cells, endothelial cells, and liver cells.
PDGF: function & origin
Made from platelets, macrophages, endothelium, and smooth muscle
Function: proliferation for fibroblast, endothelial, and smooth muscle.
VEGF
Protein involved in angiogenesis of blood vessels. It is also used in lymphocyte development, vascular dilation, and permeability.
FGF
Associated with heperan sulfate in ECM
Used for wound healing, hematopoiesis, and development.
TGF-Beta (fibronective agent)
Functions: activate bone morphogenic protein (BMP), activins, inhibins, and mullein inhibiting substance.
Origin: platelets, endothelium, and mononuclear inflammatory cells (B/T cells)
Too much will cause hypertrophic scars, systemic sclerosis, marphans syndrome, and a strong anti-inflammatory effect.
GPCR MOA 3 types
Gq:causes activation of PLC, which makes IP3 and DAG,
Gs: formation of cAMP, which causes phosphorylation of proteins in the cell.
Gi: inhibits aldenylyl cyclase, which prevents the activation of cAMP.
Basement membrane components
Collagen type 4, proteoglycan, and laminin.
RTK MOA
Akt, MAP-kinase (Ras/Raf), and IP3 pathway.
Collagen type 1: Origin & Defect
Origin: Bones
Defect: Osteogenesis Imperfecta and Ehlers-Danlos syndrome
Collagen Type 2: Origin & Defect
Origin: Cartilage, intervertebral disks
Defect: Achondrogenesis type 2, spondyloepiphyseal dysplasia syndrome.
Collagen type 3: Origin & Defect
Origin: Hollow organs and soft tissue
Defect: Vascular Ehlers-Danlos syndrome
Collagen type 4: Origin & Defect
Origin: Basement membrane
Defect: Alport Syndrome
Collagen type 5: Origin & Defect
Origin: Soft tissues, blood vessels
Defect: Classical Ehlers-Danlos syndrome
Collagen type 7: Origin & Defect
Origin: Anchoring fibrils at dermal-epidermal junction
Defect: Dystrophic epidermolysis bullosa.
Marfan syndrome
Defect in fibrillin
The patient will be very tall and lanky (Abraham Lincoln), they will have ectopic lens, and cardiovascular symptoms.
Rb gene: function
Function is to prevent the cell from advancing into S phase.
Defective will lead to retinoblastoma.
p53 function
Function: guardian of the genome, prevents cell from leaving G1 phase
Niche cell
Special type of microenvironment in which somatic stem cells live in.
Where are liver stem cells found?
Canal of Hering
Where are the brains neural stem cells found?
Subventricular zone and dentate gyrus of the hippocampus.
Labile cells
Cells that are continuously dividing (hematopoietic stem cells)
Stable cells
Cells that can divide but a limited amount of division (generally in G0 phase, liver)
Permanent cells
Cells that don’t divide (cardiac cells, stuck in G0).
