Lecture NC's for Test 2 Week 2 Flashcards
Mostly function by dimerizing in the presence of ligand and activating intracellular kinase activity
-Inactive as monomers
Protein kinase receptors
An example of desensitization of receptors is seen in the
β-adrenergic receptor
What are the 4 classes of intermediate filaments?
- ) Nuclear
- ) Vimentin-like (Desmin = Muscle, Vimentin = mesenchymal)
- ) Epithelial
- ) Axonal
What is the largest of the motor proteins?
Dynein
Regulate myosin and can be phosphorylated
-often comprised of calmodulin
Light chains of Myosin
Dynein binds microtubules through the
Stalk
The motor domain of dynein does NOT contain the
Microtubule binding domain
Defect in recognizing signal of peroxisomal proteins
Zellweger syndrome
We never find glycosylated molecules in the
Cytoplasm
Glycosylation occurs in the
Lumen of the ER
Lysosomal proteins receive their M-6-P tags in the
cis-Golgi
Lysosomal proteins bind M-6-P receptor in the
trans-Golgi
Clathrin does not directly bind to the membrane receptors. Instead, it binds
Adaptin
Keeps enzymes from leaking out into underlying tissue
Tight Junctions
Expressed highly in parts of the renal tubules where Ca2+ and Mg2+ resorption takes place
Claudins 16 and 19 (tight junctions)
What would you expect from a patient with a mutation in the tight junction proteins claudin 16 and 19?
Serum: Low Ca2+ and Mg2+
Urine: High Ca2+ and Mg2+
Cadherin mutations can lead to
Developmental disorders
Mutations in connexin 26 lead to
Deafness
Mutations in connexin 32 lead to
Peripheral neuropathies
Calcium dependent cell adhesion molecules (CAMs) with a carbohydrate recognition domain (CRD)
Selectins
Major component of the lamina densa
Collagen IV
Mostly found in connective tissue where it connects the connective tissue to the lamina densa
Collagen VII
Transmembrane collagen that anchors epithelial cells to basal lamina
Collagen XVII
Proteoglycan that has a noncovalent interaction with hyaluronic acid
-abundant in cartilage
Aggrecan
Proteoglycan with heparin sulfate GAG that is located in the basal lamina and associates with collagen IV
Perlecan
Proteoglycan with chondroitin sulfate GAG that is located in fibroblasts and epithelial cells and helps stabilize interaction of FGF with receptor
Syndecan-1
Focal adhesions form at the site of bound
Integrin
Maintains phosphotidylserine in inner leaflet
Flippase
Enzyme that causes phosphotidylserine to flip to outer leaflet
Scrambalase
Cleave ICAD to make CPAN, which oligomerizes and becomes active DNAse
Caspases 3 and 7
How can we determine a cell is autophagic?
Lots of vacuoles
How can we determine that a cell is apoptotic?
Dark color in nucleus from chromatin condensation and DNA laddering
How can we determine that a cell is necrotic?
Ruptured membrane
The TGF-β signaling pathway peptides bind as dimers to
Serine-Threonine Kinases
The FGF signaling pathway peptides bind as monomers to
Tyrosine kinases
A mutation in which TGF-β peptide will prevent formation of mesoderm and primitive streak?
Nodal
Suppresses mesoderm and nervous system formation and promotes epidermis formation
BMP-4
Leads to nodal expression on one side of the embryo and left-right sideness
-promotes noggin and chordin expression to inhibit BMP4
FGF
Embryogenesis occurs during weeks
1-3
Once a mature follicle is formed, it will discharge an oocyte. This is called
Ovulation
Fertilization takes place in the
Ampulla of the uterus
The layers surrounding the mature oocyte are mature follicular cells. The follicular cells that are left behind become the
Corpus luteum
Maintains the corpus luteum so that is can secrete progesterone and maintain the endometrium
-secreted by trophoblasts
Human Chorionic Gonadotropin
Non-cellular glycoprotein layer surrounding oocyte
Zona Pellucida
The corona radiata is also known as the
Cumulous Ooforous
What is triggered in the oocyte upon fertilization
Meiosis II
What are the two ways that the Oocyte blocks polyspermy?
- ) Instant depolarization
2. ) Intracellular Ca2+ tsunami that induces cortical reaction
Cortical granules line ZP and secrete enzymes that make it impermeable to other sperm
Cortical reaction
Have separate amniotic cavities and separate or shared placentas
-Can be same or opposite sex
Dizygotic twins
Morulla cells start to secrete
ICM and OCM
Occurs by the end of week one, around day 6
Implantation
Embryoblast cells differentiate into epiblast (top) and hypoblast (bottom) cells to form the
Bilaminar disc
Located above the epiblast layer
Amniotic cavity
Located below the hypoblast layer
Yolk sac
Insufficient amniotic fluid
Oligohydraminos
Too much amniotic fluid
Polyhydraminos
When hypoblast cells differentiate and line the trophoblast cells, they convert the blastocyst into the
Yolk sac
Allow for blood exchange between yolk sac and embryo
-where early exchange occurs
Vitelline Vessels
Germ cells from the yolk sac form the
Gonads
Waste moves from the fetus to the placenta through the
Fetal arteries (there are 2)
The mesoderm differentiates into the
Paraxial, intermediate, and lateral plate mesoderms
Differentiates into somite mesoderm
Paraxial mesoderm
Will split into the parietal/somatic layer and the splanchnic/visceral layer
Lateral mesoderm
Form when primitive steak fails to completely regress
-can contain multiple tissue types such as skin, teeth, etc
Teratomas
An area of mesenchyme that contains signals which instruct the developing limb bud to form along the anterior/posterior axis
Zone of Polarizing Activity (ZPA)
Sonic hedgehog is expressed in the
Notochord
In the adult brain, Shh is expressed in the
Hippocampus
An extra digit on pinky side of hand or feet
-Results from Gli haploinsufficiency
Postaxial polydactyly
Wnt signaling is associated with cancer, especially
Colon Cancer
Which transcription factor aids in the fusion of the neural tube?
Snail
c-Kit is which type of receptor?
Tyrosine kinase
Cardiac outflow track cells require
Crkl
Growth factors stabilize p53 through
-sequesters MDM2 (HDM2)
p14ARF
Things that inhibit the cell cycle are classified as
Tumor Suppressor genes
What are the oncogenes of the mTOR pathway?
PI3K, AKT (PKB), and mTOR
What are the tumor suppressor genes of the mTOR pathway?
PTEN and TSC
Pail membranes of the eyes
-good indicator of anemia
Conjunctival Pallor
Tells us what types of WBCs are in the population
CBC w/ differential
Enzyme found in granules of WBCs
Myeloperoxidase
How can we differentiate Myeloid cells and Lymphoid cells in a blood smear?
Myeloid cells: much bigger than RBCs
Lymphoid cells: about same size as RBCs
In the CML translocation, the Bcr and Abl breakpoints both occur in
-splicing remains in tact and chimeric protein is made
Introns
What type of mutation is the balanced translocation leading to the formation of Bcr-Abl
Gain-of-function
Bcr-Abl being trapped in the cytoplasm prevents maturation of myeloid cells and results in
Blasts
Otd and Otx1 are and example of
Orthologs
Hoxa2 and Hoxb2 are an example of
Paralogs
The vertebral skeleton
Scleretome
The skeletal muscle
Myotome
Stops the destruction complex from phosphorylating β-catenin
Disheveled
Smootheneds natural ligand may be an
Oxysterol
p14ARF is transcribed from DNA that also encodes a
CDK inhibitor
A trunicated/mutant protein can have which type of affect?
A dominant negative effect
Caused by constitutive action of c-RET
Multiple endocrine neoplasia (MEN)
How can we treat constitutively active mutations in protein kinase?
An inhibitor like Gleevec that binds near ATP binding site and prevents binding
Characterized by NC-derived intermediate cells being lost. There is no endolymph, and hair cells die
Waardenburg’s Syndrome
The main mutation causing Waardenburg’s is a mutation in
Micropthalmia transcription factor (MITF)
Expressed ion melanocyte populations such as in the iris, the skin, and the cochlear duct (supports hair cells)
MITF
Without functional MITF, there will be no endolymph in the ear and the result will be
Deafness
Located downstream of c-kit and the steel factor ligand via MAP kinase
MITF
The target genes of MITF include
Bcl-2 (anti-apoptotic) and melanin
Waardenburg II clinical syndrome may also be caused by mutations in
Slug
Not affected by slug mutation
MITF expression
On the outside of the cell and facilitates LDL binding to receptor
-mutations prevent LDL from binding receptor
Apolipoprotein B
Bind to receptors on inner nuclear membrane and to chromatin an transcription factors from the nucleoplasm
Lamins
If lamina is disrupted, detrimental effects could easily arise from mislocalization of
Proteins/chromatin
Intermediate filaments assemble as
Coiled-coil dimers
Characterized by a splice defect in lamin A that prevents cleavage of a lipid chain
Progeria
Continued farnesylation (lipid attachment) to Lamin A leads to Lamin A incorporation into
Nuclear envelope
Atypical-Werner’s syndrome could result from altered helicase attachment site in
Lamin A
Interact as a complex with clotting factors V and VIII
LMAN and MCDF2
Without either LMAN or MCFD2, clotting factors V and VIII can not be incorporated into
COP-II vesicles
The myosin Va link to the melanosome is abolished in
-shows neurological problems
Griscelli type I
How does a melanosome attach to myosin Va?
Rab27 binds melanosome first, then melanophilin binds, then myosin V
The Rab27a link to the melanosome is disrupted in
-shows immune problems
Griscelli II
By and large an inhibitor of cell division because smad transcription factors activated by this signalling promote synthesis of CDK inhibitors
TGF-β signaling
Are typically both necessary and sufficient to generate specific body parts and/or cell types
Homeobox transcription factors
The Philadelphia chromosome (short Ch22) gains genetic material from
-results in the production of abnormal protein
Chromosome 9
Another name for hematopoetic stem cells is
CD34 positive cells
