Robbins Ch. 1 Flashcards
Which histone residues can be methylated by specific writer enzymes?
Lysines and Arginines; in particular lysine associated with either transcriptional activation or repression
What histone residues are acetylated?
Lysine
What actylates histones and what does this do?
Histone acetyl transferase (HAT); open up chromatin and increase transcription
What deacetylates histones?
histone deacetylases (HDAC); condensation
What histone residues are phosphorylated?
Serine residues
What does DNA methylation typically result in?
transcriptional silencing
What enzyme trims primary miRNA?
DICER
Where are proteins destine for the plasma membrane or beyond sythesized and physically assembled?
RER; golgi
Where are proteins intended for cytosol synthesized?
SER
What phospholipid is on the inner membrane can be phosphorylated, serving as an electrostatic scaffold for intracellular proteins? can also generate DAG and IP3
phophatidylinositol
What phospholipid is usually on the inner membrane but when it flips to the outside it is an “eat me” signal for phagocytes?
phosphatidylserine
What phospholipid serves as a cofactor for blood clotting on platelets?
Phophatidylserine
What phospholipids are preferentially expressed on the extracellular face and are important in cell-cell and cell-matrix interactions, including inflammatory cell recruitment and sperm-egg interactions?
Glycolipids
What is the Transporter ATPase which pumps polar compounds (i.e. chemotherapetic drugs) out of cells and may render cancer cells resistant to treatment?
Multidrug resistance protein (MDR)
Familial hypercholesterolemia is due to a defect in what?
receptor-mediated transport of LDL
What type of cytoskeletal proteins have characteristic tissue specific patterns of expression that can be useful for assigning a cell of origin for poorly differentiated tumors?
Intermediate filaments
What motor protein of microtubules is responsible for anterograde transport?
Kinesins
What motor protein of microtubles is responsible for retrograde transport?
Dyneins
What is defective in cystic fibrosis?
absence of a single amino acid of the CFTR protein which leads to misfolding, ER retention, and degradation. Also, excess accumulation exceeds the capacity of the ER to respond leading to apoptosis.
Which cells have an especially prominent golgi complex?
Goblet cells of the intestine, bronchial epithelium, and plasma cells
What type of cells have more smooth ER?
Cells that synthesize steroid hormones (gonads/adrenals) or that catabolize lipid soluble molecules (liver)
What are lysosomal enzymes tagged with?
mannose-6-phosphate
Things marked with ubiquitin are destined to be digested by what?
proteosomes
What mitochondrial inner membrane protein can use the electron transport chain to produce heat instead of ATP?
thermogenin
Explain the Warburg effect
Pure oxidative phosphorylation produces abundant ATO but also uses up all glucose leaving no building blocks. So, rapidly growing cells (both benign and malignant) upregulate glucose and glutamine uptake and decrease their productin of ATP per glucose molecule.
What signaling pathways are associated with growth factor signaling pathways that drive cell proliferation?
Tyrosine kinase and GTP binding
What type of signaling is associated with pathways that regulate normal development?
Triggering a proteolytic event or change in protein binding or stability that activates a latent transcription factor
Name the Growth factor: Mitogenic for keratinocytes and fibroblasts; stimulates keratinocyte migration; stimulates formation of granulation tissue
Epidermal growth factor (EGF)
Name the growth factor: stimulates proliferation of hepatocytes and many other epithelial cells
Transforming growth factor-alpha (TGF-alpha)
Name the growth factor: Enhances prolferation of hepatocytes and other epithelial cells; increases cell motility
Hepatocyte growth factor (HGF) (scatter factor)
Name the growth factor: Stimulates proliferation of endothelial cells; increases vascular permeability
Vascular endothelial growth factor (VEGF)
Name the growth factor: Chemotactic for neutrophils, macrophages, fibroblasts, and smooth muscle cells; activates and stimulates proliferation of fibroblasts, endothelial, and other cells; stimulates ECM protein synthesis
Platelet-derived growth factor (PDGF)
Name the growth factor: chemotactic and mitogenic for fibroblasts; stimulates angiogenesis and ECM protein synthesis
Fibroblast Growth factors (FGFs), including acidic (FGF-1) and basic (FGF-2)
Name the growth factor: chemotactic for leukocytes and fibroblasts; stimulates ECM protein synthesis; suppresses acute inflammation
Transforming growth factor-BETA (TGF-BETA)
Name the growth factor: stimulates keratinocyte migration, proliferation, and differentiation.
Keratinocyte growth factor (KGF) (FGF-7)
What growth factor receptor mutations frequently occur in a number of cancers including those of the lung, head and neck, breast, and brain?
EGF and TGF-alpha; EGFR1 tyrosine kinase activity
What is the receptor for HGF?
MET
What diseases are associated with over expression of MET?
Renal and thyroid papillary carcinomas
Antibodies against VEGF are approved for treatment of what?
Renal and Colon Cancers and a number of ophthalmic diseases
What are the 2 basic forms of ECM?
Interstitial matrix and basement membrane
What are the 3 groups of proteins that make up the components of the ECM?
1: Fibrous Structural proteins
2: Water hydrated gels
3: Adhesive glycoproteins
Osteogenesis imperfecta and certain forms of Ehlers-Danlos syndrome are due to genetic defects in what?
collagens
What type of collagen is type IV?
non-fibrillar
Fibrillin synthetic defects lead to what?
skeletal abnormalities and weakened aortic walls as in individuals with Marfan syndrome
What is the most abundant glycoprotein in the basement membrane?
Laminin
